Here's what Tom Arnold's mouth says about his forthcoming divorce from wife Roseanne: 'I do know that the marriage is over. And I do know that our relationship is over - and that's good. I know that I am capable of loving other people, that I'm capable of having fun with other people. It's really better this way.'

Here's what Tom Arnold's body says about his forthcoming divorce from wife Roseanne: hands clench and unclench. His left leg moves back and forth like a piston, lifting the rug beneath his feet, turning it into a tiny rug mountain. The sofa begins to . . . well, not shake exactly. It's more of a vibration, a tremor, a spasm from somewhere deep down.

It's just possible that these physical tics are an unwelcome legacy of a regretted past - the comic is a recovering alcoholic and drug addict (coke, since you ask). But as the name Roseanne triggers the most extreme fidgets, it's more likely that Tom Arnold's body simply doesn't agree with the lip service being paid to letting go and moving on and all that mature adult bullshit. No matter what the mouth says, Tom Arnold's body behaves as if it's still in love.

Is that it? Is he still in love with the sitcom superstar? Despite the accusations of assault? Despite claim and counter-claim on the family fortune (Arnold is asking for dollars 65,000 a month, Roseanne wants their two production companies and her Emmy award back)? Despite the public humiliation of travelling to Europe to patch things up and finding her with another man?

Arnold starts to say that his grandparents were married for 60 years and that he expected his marriage to endure, too - for better, for worse, in sickness and in health. That's the deal, isn't it, a lifetime contract, not a month-to-month deal? Then he turns his head away to hide the welling tears. When he speaks his voice gives everything away.

'One thing I've never done, and am never going to do, is to talk negatively about Rosie. And I won't respond to anything, cause you know, that makes it worse. When you love somebody more than you love anybody in the world, how can you hate them the next day? You can feel rage and you can feel hurt and you can feel sad, but that is because you feel let down and abandoned. It's not because you don't love the person. You can't make them out to be something that they weren't. Rosie was very supportive of me and loving and I loved her and . . . and I'm just sorry it didn't work out.'

Still, it all hurts, particularly the wife-beating charges. He tries to be decent about it. 'Divorces are real emotional times. Sometimes you say things you don't mean. And there's been a lot of turnover in her camp, a lot of new people around, a lot of new influences. There are just people who like to stir things up.

'Look, I know what life has been like for five years of our marriage and I know how good it was, and that sometimes it wasn't good, but when it was good it was the best thing I ever had, and I still have those feelings in my heart, and that stuff is outrageous. I don't respond because it's . . . I assume that everything will be taken back.'

A fair assumption on past record. The battery charges were withdrawn and apologised for after the first divorce petition collapsed in April, only to be renewed the day before Arnold's movie, True Lies, opened in the US. That's what he's in London to promote: his scene-stealing, co-starring role in the Schwarzenegger vehicle (coming to a cinema near you soon). He's proud of his lauded portrayal as Gib, the coarsest sidekick ever; it's the part that finally convinced the US media that he's talented and hasn't been hitching a ride on Roseanne's coat-tails, an idea of such wide currency that at one point Arnold was the most irrationally loathed man in America.

Loathed because he supposedly came from nowhere (he'd been respected on the stand-up circuit for years) and snatched the nation's blue-collar heroine away from hearth and home. The truth is that Roseanne's previous marriage had been in trouble for some time and Arnold had been a friend for over a decade.

But it was his promotion to executive producer on the Roseanne show - he'd previously been a writer - amid mass sackings that sealed the fate of his public persona. The fact that the series improved under his reign was discounted as the public confused Arnold with Arnie, the fat, lazy and loud hanger-on he occasionally played on the programme.

'I was an easy target,' Arnold shrugs. 'A couple of weeks before True Lies opened I read lots of articles about how my career was over, that I couldn't act, wasn't funny, stuff like that. Rosie's supposed to have done everything for me. Now the reviews are in and they look stupid. Boy, how stupid they look.'

In America audiences for the film have been booing his opening screen credit, but by the end they cheer a personal triumph denied him by the inexplicable twin failures in America of the television sitcoms The Jackie Thomas Show and Tom.

Still, this is also the role that took him away from home for months, away from the other roles a vulnerable woman expected him to play: husband, manager, loving stepfather to her children and a loving father/protector to herself.

And Roseanne needed protecting. She was hospitalised at 16 after a childhood marred by what she describes as wholesale violent and sexual abuse. She has never made any secret of her sometimes precarious mental balance. Indeed, the title of the second volume of her autobiography, My Lives, is a tribute to her multiple selves (she lists 19). Having suffered childhood abuse himself (his mother married six times and ran with a rough crowd, his father believed in regular beatings), Arnold understood and shared his wife's desperate need for stability. They were a sort of Perfect Imperfect couple.

From the outside, it often looked as if the two of them were venting a lifetime of agony and rage at the world around them: the public feuds with other stars, the shuttling back and forth between agencies, the shedding of managers, the resulting lawsuits, the mass sackings. Arnold doesn't regret the sackings that first earned him a bad name - 'I can't think of one person who got fired who didn't deserve it' - but otherwise he looks back in ambivalence.

'We had a lot of 'us against them' going. It made us feel pretty comfortable to be in that position. It also wore me down. The lawsuits, the battling with people . . . I couldn't do it any more. I couldn't have any more arguments.

'I think Rosie had so many battles with people because her childhood was so bad. But she needed to have somebody on her side. Right or wrong, I was the guy by her side. I was happy to do it. It made me feel good. I think all husbands do that, don't they? Protect their wives? If Rosie was having a problem with somebody, then that was my problem, too.

'I think when you're married longer you can be a little more objective about that. You can have your own values, your own point of view, even when you're supporting your wife. You have to figure out a way in your own mind to take your own side, too.

'But there's a problem when you're fixing everything. One day you want to slow down and work on something more independent and the other person can feel abandoned. You're going out of town to do a movie and it's 'what about this stuff?' and 'what about what's going on here?' It's a natural thing. It's how I would feel. Maybe that's how Rosie felt. I don't know.'

Arnold doesn't even know which one of his wife's various identities has instigated the separation. 'Well, I'm sure there's parts of her that don't want to get divorced and you have to decide whether those are the healthy parts or the sick parts. But the whole of Roseanne is divorcing the whole of me. You know there are things inside of me that say maybe this is a bad idea; try to do everything you can to manipulate it so that you don't get divorced. But those are not necessarily my healthiest thoughts. I know that.'

It's 'cool that she has someone new' and that the new series began shooting last week minus his input, because he knows Rosie is a great star and good person. But those unhealthy thoughts dog him. 'If you have a serious mental illness in a relationship - in anything - then it adds extra variables. And I think there are times when people take advantage of that, you know. They push buttons and get the reaction they want. And it hurts . . . it hurts. I just feel really bad for her.'

He saw her a couple of weeks ago though, face-to-face and it felt 'fine'. 'We talked about stuff. It was nice. That's why I think everything will go smooth. Rosie has someone she likes now and I have someone I like, too.'

So if Rosie rang right now and said big mistake, take me back? 'That has happened. I think it's best if we don't get back together. That's how it needs to be. I'm getting on, she's moving on. It's positive.

'Yeah, I worry about her. But that was my job before and it's not my job to do that now.' Tom Arnold turns his face away again.

(Photographs omitted)