It's always fun and games on the work front, but behind the scenes, 2015 was a challenging year for Alan Carr. The Chatty Man tells Hannah Stephenson why he feels he's finally found a 'happy ending'

Alan Carr greets me in typical effervescent form, eager to regale his woes via amusing anecdotes and trademark self-deprecating wit.

After a mammoth tour of Australia, he and his partner - party planner Paul Drayton - have just returned from a holiday in Bali and Lombok, and Carr is sporting the engagement ring Drayton gave him during the trip.

The host of Channel 4's Chatty Man talks as if he's doing a stand-up routine, moving quickly from one funny story to the next, often ending in a punchline you feel he's delivered before.

Many of his hilarious anecdotes are featured in his second memoir Alanatomy, which reads a bit like one of his stand-up shows, full of Carr mishaps and mirth.

But there are excerpts of the book - a follow-on from his first bestselling autobiography Look Who It Is! - which simply aren't funny, no matter how hard he tries to make light of them. Last year was undoubtedly his annus horribilis.

His partner's alcoholism and spells in rehab, Carr's own dubious relationship with booze, along with the crippling anxiety attacks for which he sought help, are all charted in the book, and while he does his best to keep the mood light, it's clear 2015 was a desperate time for the comedian.

Matters came to a head at his pal Adele's fancy dress birthday party. Carr dressed up as Purple Rain-era Prince, while Drayton squeezed into a pencil skirt and high-heeled boots, dressed as his mother, and in doing so managed to pull the vertebrae in his back out of line. He then developed deep vein thrombosis and an embolism.

Drayton was bed-bound for weeks and, overnight, Carr turned into his reluctant carer. "In my head, I thought I could be his nurse, but he did my head in.

'I would turn into Kathy Bates in Misery, you know, that 'cockadoodee' woman. I started crushing Nytol into his food."

Carr says he and Drayton had always liked a drink but when Drayton injured his back, he was simply drowning his sorrows at home while Carr went to work, doing the chat show and a big UK tour, and the comedian just couldn't keep an eye on him.

"When people think of alcoholics, they think of Patsy from Ab Fab having a whale of a time. But you're watching someone kill themselves slowly. I couldn't cope because when I left the house, I didn't know if he was going to have a fall, or put something on the hob and fall asleep."

He writes: "When I did come back to the house, I saw how many bottles had been consumed. I wasn't particularly worried about the wine, it was the empty bottles of spirits, gin and vodka which I found alarming."

He says now he considered leaving, as he couldn't envisage spending the rest of his life with an alcoholic invalid - but the experience also led him to question his own drinking habits.

While all smiles on his chat show, behind the scenes, Carr's life was falling apart.

"I'd come home and end up having a bottle of wine because I couldn't cope."

There were times when he thought he was an alcoholic, he says, but when he saw his partner in a worse state, he realised he was nowhere near it.

"You start to understand that alcoholism isn't really about drinking," he writes, "it's about control, habit, self-worth, depression, escape...

"I soon found out he had been drinking in the mornings. I took a sip of his 'water' from his side table and my body instantly repulsed as the recognisably harsh taste of vodka kissed my lips."

Drayton wasn't a "fun drunk" towards the end, he adds: "He was grey and shuffling around. It was like watching someone die."

The first time he entered rehab, Carr put him there, he reveals. The second time, however, Drayton asked to admit himself, and at the time, Carr thought their relationship was coming to a head ("I said, 'It's over. I don't want to go out with an alcoholic for the rest of my life'.").

The stress also caused Carr to hit the bottle big-time, he reveals.

"I was drinking too much, although I hadn't got to the stage where I was knocking on Wetherspoon's door at 11am saying, 'Let me in, I fancy a pint'."

He also suffered anxiety attacks, which culminated in imaginary bladder problems.

"I had a meltdown when I turned 40, a mid-life crisis," Carr explains. "I was drinking too much and I was losing my spark a bit. I started to become a bit flat. I put on loads of weight."

He had a number of tests to analyse the bladder problems - in which he had the sensation of wetting himself on stage, even though he wasn't actually doing so - which all proved negative.

"When I got the tests back and was all clear, I thought, 'Oh no, it's in my head'. If they did a celebrity special of Embarrassing Bodies, I'd be on it. It'd be a two-parter."

He sought therapies, including meditation, healing and Reiki.

"I ended up doing some healing, which I didn't want to do. It's all in your chakras, isn't it? You know, where your stomach is your second brain.

"The only thing I didn't do was hypnotism, because I didn't want to end up walking down the street hearing the Birdy Song and start taking my clothes off.

"But when I know I'm on live telly and I've a busy schedule, I go to therapy, which helps."

Today, Carr is in a better place. Drayton is out of rehab, and they are happily engaged.

"With alcohol you are never yourself - there was party Paul, hysterical Paul, upset Paul, morose Paul, exuberant Paul. Nowadays I get just Paul, and I like it like that."

"The fact he's given up drinking has been great for me. I look back and I think I was a bit stupid, really.

"I still have a sneaky drink when I'm out with friends but I don't drink in front of him. Last year was a roller coaster but I feel it's a happy ending now."

The forthcoming wedding is likely to be a celebrity-filled bash. He's good pals with a lot of famous folk, including Adele, Gok Wan and Melanie Sykes, but says: "I'm not cut out in that celebrity cloth. I don't do the red carpets."

While marriage may be on the cards, Carr has no desire for children.

"I know so many gay men who want to be dads, and I thank my lucky stars that I haven't got that, neither has Paul. "

Work keeps him busy enough. He'll be doing a Christmas special of Chatty Man and has his fingers in other pies. He set up his own production company this year and is making a new Channel 4 show, Alan Carr's Happy Hour, a pre-watershed series featuring a mixture of games, sketches and stunts alongside celebrity guests.

And he will always return to stand-up.

"I find stand-up so pure and it gets rid of the politics of this whole showbiz thing," says Carr. "It's just me going on stage with a mic into the darkness. I love it and I need it."

Alanatomy by Alan Carr is published by Michael Joseph, priced £20. Available now