Brittany Cartwright is bra-free as she almost spills out of low-cut dress at Kathy Hilton's Christmas party

Brittany Cartwright put on a sexy display while at Kathy Hilton's Christmas party in Bel Air, California.

The 35-year old was bra free as she wore a plunging bright red strapless gown.

The ex of Jax Taylor showed off her tiny waistline while posing by a Christmas tree.

She also posed with RHOBH star Hilton as well as several of her female friends at the holiday bash.

Months ago she lost weight with diet and body contouring from AirSculpt.

Cartwright has been battling her weight ever since she welcomed her son Cruz.

She has tried Jenny Craig, which caused her to lose 40lbs; soon after she modeling swimsuits for Cupshe.

But she felt like she wanted some extra weight removed from around her waist. 

In September Cartwright told DailyMail.com exclusively she had a two hour AirSculpt session - which removes fat and tightens skin - in May so she could feel good about her body for the summer.

The work was done three months before filing for divorce from Taylor. And the reality TV sensation is 'thrilled' with the move that has boosted her confidence after a very tough year. 'I am feeling great these days after getting AirSculpt,' she told DailyMail.com as she could be seen showing off her slender frame in new images.

'Yeah, you can say I wanted a revenge body. I wanted to look good after everything I’ve been through this year. I want to look my very best. I wanted to get my sparkle back.'

This comes after she said she doesn't regret having a fling with one of Taylor's friends. In October, PageSix claimed the man who caught her eye was Julian Sensley, 42.

The star insists she didn't plan to 'hook up with his friend' - but Brittany doesn't have any regrets about it, either.

Brittany - who split from Jax earlier this year - said on the Hot Mic podcast: 'Jax and I did not have a no dating in the friend group policy.

'We never spoke about that because why would we? First off, I didn't think I was going to hook up with his friend. It wasn't planned. I wasn't trying to go after one of his friends. That's not how it happened.' 

Brittany also admitted to having a flirty exchange with the man on social media.

She said: 'I could tell this guy was flirting with me. I was always flirting with him. He's very much my type.'

Jax previously admitted that he doesn't blame Brittany for seeking a divorce.

He said on the When Reality Hits podcast: 'Unfortunately, she's had enough. And I don't blame her at all. 

'I mean, I can't believe she's been with me this long as it is. That we stayed, to be honest.'

Despite this, Jax was still caught off-guard when Brittany decided to leave him.

The reality star - who has Cruz, three, with Brittany - said: 'When she decided to leave, I was kind of in shock. I shouldn't have been in shock, but I was in shock.'

Jax also conceded that he's been through a 'really, really rough' time since his high-profile split from Brittany.

Jax - who spent some time in rehab earlier this year - added: 'Anyone that has gone through a divorce will understand how difficult this is.'

She also said she doesn't think Taylor changed 'at all' during his spell in rehab. 

The star spent time at a mental health facility earlier this year, but Brittany doesn't feel it's had any impact on him and she doubts whether he even has the capacity to change. 

Brittany said on the 'Hot Mic' podcast: 'I don't feel like he changed at all in those 30 days.

'And the reason, I mean, I'm sure it'll be on the show as well, but, you know, a lot of rage texting and stuff was still going on the entire time that he was in rehab.

'So, for me, I was just noticing like, this is just going to be constant. Like, if you're in therapy seven hours a day, and you're still finding time to call me names and cuss me out? And send me rage texts? 

'Then you're obviously not ever gonna change.' 

Although Brittany subsequently admitted that a reconciliation remained possible, she confessed to being tired of 'cleaning up Jax's messes'. 

The former Vanderpump Rules star - who filed for a divorce from Jax in August - told Us Weekly: 'There's definitely a chance. But I won't waste my time and get back into a toxic situation.

'Now the veil has been lifted and I see how much I was always cleaning up Jax's messes. I'm thrown in the middle of all these fights and constantly forced to apologize for him in the media and to friends. It's hard.'