Friend [34F] is marrying her long term abusive partner [35M] and has asked me [34F] to be maid of honour. I don’t support the marriage. How do I decline?

Hi Dating.mobi, long time subscriber to this sub, and today I need your help. I’m using a throwaway as I’d rather not have this linked to my main. I’d love some help navigating a situation I’m currently in. I’m sorry this post is so long.
I have a friend, we’ll call her Louise, who I’ve known for close to 30 years now. We’re the kind of friends who can go a year without speaking, and when we do nothing will have changed.
About 14 years ago Louise got Together with Steve. The relationship was volatile from the start, but Louise fell pregnant and they decided to try and make things work. Steve is the most selfish and entitled person I’ve ever met, a true narcissist and all round horrible human being. I’ve witnessed his emotional abuse countless times, I’ve seen him punch and kick holes into walls, throw objects at undeserving people, get into physical fights, because he can’t control his anger. According to Louise, he’s never been violent towards her, but I’m not convinced. He’s a terrible father to his son, who’s now 12, and they’ve never had a good relationship. Heartbreakingly, when their son was around 8 or 9, he told me that he wished it was just him and his mum, since he knew his father hated him.
Over the years, Louise has left Steve a few times. But she always goes back. The typical abused partner. She relies on his parents for childcare (Steve has never looked after his own son, never even changed a nappy) and his parents become very manipulative towards Louise when they’re broken up. I offered my support for many years until I just couldn’t excuse it any longer, since her choices were ultimately affecting her son, and I distanced myself about 5 years ago, only catching up once or twice a year. When I do speak to Louise now, Steve has warned her not to discuss their relationship with me, complaining that she always tries to leave him after she’s spent time with me. The last time I saw Steve, a couple of years back, was during a time that I was secretly helping Louise to leave and begin a new life with her son. She ended up taking Steve with her. They’re still together, living in a house she owns by herself.
In the last year or so she’s lost over half of her body weight. Medical tests have shown there’s nothing physically causing this, and I suspect she’s dealing with an eating disorder.
Today I get a phone call from Louise. She and Steve are getting married in six months, and she wants me to be her maid of honour. It hit me like a bolt out of the blue. I told her I loved her and I wanted her to be happy, but that I was not Steve’s greatest fan, and I asked why after all this time she wanted to get married. She said Steve’s changed, they are finally happy and their son is doing well and it feels like the right time. If Steve’s ‘changed’ it simply means he’s given up drink/drugs and is finally able to maintain a job and contribute financially to the family, he has certainly not had any therapy or professional help.
I pointed out that their wedding date will take place three weeks after I’m due to give birth to my first child, and I’ll need to think about whether I can realistically take on this role.
The reality is, I hate Steve, I hate what he’s done to my friend, even more I hate the effect it’s had on their child, and I do not support this marriage in any way.
I don’t know what to do. I don’t even want to attend the wedding, never mind standing next to her whilst despising the absolute piece of **** that she’s choosing to be legally bound to.
How do I communicate this to her? My SO says I should just blame the fact that I will have a newborn, and that only negative things can come of me telling her the truth, and I should avoid hurting her. I’m reluctant to lie in this way, but I see where he’s coming from. What should I do?
Tl;dr my oldest friend is getting married to her long term abusive ******* of a partner. Wants me to be her maid of honour. I don’t support this marriage in any way. I’ll have a three week old newborn when the wedding rolls around. How do I break the news to her that I simply can’t do this?
Edit: I’ve just woken up and wanted to thank everyone for their input and thoughtful responses, it’s really helped to clear up my thoughts on the matter. For a start it sounds like I’m being a bit naive as to what I’ll likely be capable of with the pregnancy/newborn! Most importantly, I realise I have to tell Louise the truth.
It dawned on me that Louise normally works full time, but for the last six month or so has been on long-term sick leave from work. This is probably the reason why things seem better from the perspective of her and Steve’s relationship. With no job, she’ll have been keeping up with the housewife duties without any need for Steve’s support, and this will have been keeping his anger at bay. It’s not sustainable in the long term, unless she’s locked in the house 24/7 and they can survive without her income (which they can’t). This realisation only strengthens my feelings that I can’t do this.
I plan on writing her a letter, telling her that I love her and will be here for her no matter what. But I will explain why I cannot celebrate this. There will be no surprises, it’s nothing I haven’t told her before, many times. I don’t expect her to leave him, and I’m prepared for this to affect, and possibly destroy, our friendship. But as I said in my post, I drew the line when I started to see the impact her choices were having on her child.
Thanks everyone, you’ve all helped more than you’ll ever know. If there ends up being a meaningful update, I’ll be sure to pass it on.


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