I have horrifying cholesterol levels," says Rufus Wainwright, noting burrata on the menu at La Petite Maison in Mayfair and wondering whether to order the rich, creamy cheese. "I should be dead at this moment," he says, but telling the waiter he'll start with the burrata anyway, followed by lamb cutlets. "I've tried to be a vegetarian as well, but I keep falling off the horse and, like, eating it. My boyfriend is a vegetarian and I admire him tremendously so I've tried to find a way to do it. But I have a sorta monster in me."
As an admirer of Wainwright's music, it's hard for me not to hoot at the understatement. He has sung of personal demons ever since a debut album of piano-led ballads in 1998. Dressed today in muted grey jumper and colourful scarf, he is the laureate of monsters-in-me, and fans know his troubles well. The folk-singer parents, Kate McGarrigle and Loudon Wainwright, who divorced when he was young; the realisation that he was gay, aged 13 and at the height of the Aids scare; the addiction to crystal meth in his 20s.
"You get to a certain age," says Wainwright, now 39, surrendering his menu, a healthy-ish lentil starter added to the order, a side of broccoli to go with the lamb, "and you feel the need to reward yourself just for existing. But it's a paradox, because the rewards are also kinda killing you." He laughs, a big throaty cackle deployed often, to redivert earnest turns in conversation as well as to signpost sarcasm. "I don't want to end up on pills before I'm 40," he says, and so will start a diet as soon as he's away touring the new album.
It's called Out of the Game, and Wainwright is plain about his hopes for it. He wants a hit, "a true, unabashed public success", in part so that he can fund his more esoteric projects. The night before our lunch he was performing at the Barbican, a musical interpretation of five Shakespeare sonnets sung with an 80-piece orchestra. In 2009 he staged an opera, Prima Donna, and is now working on another. "I want to carve out a serious period of time to focus on the next opera without any distractions," he says. "And to do that you need money."
Our starters arrive. "Starving!" sings Wainwright, getting to work on the lentils. Does he expect Out of the Game to be a final pop release before he embraces the highbrow full time? "If it ignites something," he says, "who knows? Either way I have a choice. Go with [the pop], or go on with this wonderful other career that I've built for myself. Singing Shakespeare sonnets, and writing operas, and, uh, fathering children." Wainwright had a daughter, Viva, last year. "We'd talked about it for many years," he says of the platonic conception with a friend, Lorca Cohen, daughter of singer Leonard. "Lorca wanted to be a mother but didn't want to be married." And Wainwright?
At the time his mother was terminally ill with a rare form of cancer, clear-cell sarcoma. "Lorca's clock was ticking and my mother was dying. I did actually ask my mother what her thoughts were on this, and she said in no uncertain terms: 'Rufus, you must!'" Viva was born in February 2011, just over a year after his mother died. In one track on the album, Montauk, Wainwright imagines his daughter coming to the home in Montauk, New York, where he lives with his boyfriend, Jörn Weisbrodt, Hamburg-born creative director of an arts centre in the Hamptons. In the song Viva is older, and gets to know her two dads as they live their lives: wearing kimonos, pruning roses. "My daughter is primarily with her mother," Wainwright tells me, "and it will be that way for a long time. Until she comes running to daddy as a teenager."
For now, "I've seen her a dozen times within the year", which he feels is a lot, given the circumstances of non-romantic parenting. When he heads off on tour he anticipates seeing Viva even less. "My attitude right now has to be a little cold. I'll miss a lot of magic moments, and it's very tragic. In the music business, to survive for so long, you have to be able to cut off from your emotions sometimes. And being a father you're faced with that situation. I know that my father was, with me. I understand why he had to be distant, because to rip yourself away, time after time, is almost more devastating."
Wainwright's parents separated when he was three. He says that his earliest memory is of "seeing the family dinner table being put into a removals truck, and not quite understanding what was going on". The split, he says, came down to their polar stances on how to juggle music and family. McGarrigle slowed a promising career to mother Rufus and his sister Martha (also a musician) to become a maker of memorable Irish stews and an advocate of family meal times. "The energy my mother could've focused on album-making, on her rise to fame, it had to go somewhere and it kind of went into the porridge."
Meanwhile, his father kept album-making, rising in fame. "God bless him, when I would go visit it would be a totally different vibe. Macaroni cheese from a box and the ballgame on TV. Ultimately I think my mother took the better road. But my dad decided to continue the slog, y'know, and I think, oddly, at this point, I admire him for that." How so? "His career, what he's been able to do, how great he performs still. He's really kept his voice."
A brutal assessment, this gauging of divorce in terms of career feats. Yet it's typical of his conversational manner. He is frank, sometimes breathtakingly so. Discussing a standout song on the new album, Sometimes You Need, he ends a story about his mother's failing health by saying: "Whatever. I got a song out of it."
This professional approach to the upsetting and personal – is it his way of organising difficult memories? Wainwright considers his answer. He makes neat portions of lamb, a bit of aubergine, a bit of tomato, on his fork. "I think it's just a sense of survival," he says at last. "I was faced with some pretty big questions early on and had to learn to deal with them."
He has spoken in the past about a traumatic encounter in London when he was 14; he met a stranger in a bar and was raped. "I came out of the closet very young," he says now, "and I had to cut my teeth pretty fast."
A happier thought: in August he will marry Weisbrodt. Wainwright proposed several months ago, over a kebab at a London restaurant. "I love him and I'd like to spend the rest of my life with him. But probably the reason that activated it most for me was the situation with my daughter... Our daughter. Biologically he's not connected to that child at all. Nonetheless he'll put a lot of time and emotion and effort in, and I want it to be official, for both him and her."
Wainwright has polished off his lamb and is working on the broccoli with his fingers. "I'm eating a lot here," he says, cholesterol in mind. "Isn't it terrible?" But it's not, at all. Interviewers who met Wainwright 10, 15 years ago, when he was in the depths of an addiction that inspired several great songs and ravaged his body, all said how painfully thin he was. It's heartening to see him cheerful, healthy-looking, even a little plump. He has a husband-to-be, a "perfect" daughter, a multifaceted career and a bellyful of burrata to boot. Does it feel like he's in a good place? Wainwright, as ever, resists the sentimental answer.
"Once you get to the bigger questions in life, the marriages and the deaths and the births, you have to sorta be there. You have to be present," he says. "And so it's all about maintaining respect for your demons. Whether it's writing an opera, or getting married, or having a child, there's a certain amount of me creating obstacles – to prevent me from going to the dark side."
We call for the bill.
• This article was amended on 23 April 2012. The original said that Viva was born in February 2011, only weeks after Rufus Wainwright's mother died. This has been corrected.
