Feeling sad and helpless, ruminating on fiancé's childhood trauma

[LieInsAreExtinct]

Hi, I met my partner just over a year ago on a dating app, and things moved quite fast. He moved in with me in August, and we're engaged. We're both late 50s, divorced for a number of years, and I have two adult DC, one almost 20 still at home.
Very soon after we met he told me he had been physically and emotionally abused by both his parents as a child and had run away a lot, then continued to have an unstable time, including staying with an uncle who gave him cannabis at 16 and moving around various temporary homes. He had struggled with mental health in his late 40s and finally sought help, getting 2 years of psychotherapy for complex PTSD.
He is an amazing person, I wonder how he is even alive with some of the things he went through, and although some of the trauma clearly still does affect him at times, he feels like the therapy 'worked', he doesn't have nightmares or flashbacks, he succeeds in work, he doesn't dwell on the past. He has extremely limited contact with his mum, and none with his dad. He has limited contact with his 3 younger siblings, but more because of age gap, distance, busy lives and the fact he left home by 16, than any major fallout. (He's very fond of one of his brothers in fact.)
Me? I've found it really hard to deal with, I get tearful quite often, have hostile feelings towards his mum, and find myself ruminating over it and visualising his abuse. What makes it worse is I work in MH and read a lot of histories , which constantly trigger these thoughts. I also feel it's selfish of me, having had a reasonably happy childhood, to get miserable about his. I have told him but he just says 'All of that happened a really long time ago'. I know this is true and it's part of the therapy to separate 'then' and 'now', but it's all new to me, and the hurt and shock is fresh. I feel it's having a negative effect on us both, me getting tearful and sad when we're having loving moments, as well as general low mood at other times. I don't want to either stop him from telling me things or pressure him into talking about things when he would rather not. There are some details I really wish he hadn't told me, on the other hand I want to know everything about him. Any ideas or suggestions for me to deal with this better? TIA

Like this pp I'm wondering why you need counselling? It must be quite odd to him that you're getting so upset over things that happened to him such a long time ago. It's a bit me me me if I'm honest. Sorry.

Thank you, I didn't think I was particularly sensitive, not usually the most soppy sentimental person out of all my friends, but about average! I think it may be because of the strength of love I feel, it's all hormones and enzymes and stuff going on. I have had some bereavements in the last year so could also be contributing, as well as general time of life, half empty nest, etc.

Well I can't really explain it, it's just there, and it's bothering me how I keep getting tearful. If you don't understand that, I don't think you can help

I know this. Sometimes he does suffer emotionally, and I can be a supportive partner without trying to be his therapist. We all have our shortcomings. I cannot discuss this with anyone I know, other than in the vaguest terms. That's why I am here.

separate to this OP, what is your current and past mental health like?

The bit I took from your opening post, OP, is this:

'he doesn't dwell on the past.'

I don't think you should either, and if you need counselling to achieve that goal, then go for some counselling.

By the age you both are most people have had to deal with major life events, which often include a traumatic or abusive past. It sounds like your boyfriend has effectively dealt with his. Now you need to find a way to put it behind you too.

Also, everything you hear about is new to you, whereas he's had decades head start and professional help in processing all of this.

Being deeply empathetic and affected by other people's pain isn't a bad thing and you probably can't just get over it without some time and someone to talk to.

How can I be furiously agreeing with you when I pulled you up on your own quote? Weird...

I think it's been pretty solid. I had a heartbreaking, long drawn out breakdown of my marriage due to his unresolved issues leading to addiction, and certainly shed tears over that for quite a while. Had some counseling (mainly to strengthen my resolve against taking him back.) That was 13 years ago.
But other than that I have just had usual hormonal ups and downs, never anything serious.

Echoing PPs, you've moved way too fast here. You've only known each other a year... it's probably at least two years before you really start to see what someone's really like.

You have a teenager at home too who needs protecting from the fallout of a relationship that may not work.

The worst thing here, though, is that you're not emotionally resilient enough to cope with his past. You probably need to ask yourself why you've become so focused on it.

Well I don't know why, I guess that's why I am here. I'm In love, I may be less emotionally resilient than I have been at times (I suggested some reasons for that) I think I am asking for help with the emotional resilience rather than questions about the relationship itself, because I have been through all the questions and I am as sure as anyone can be that we're good together.
Also if his mum phones (rare) or we visit her (rarer) I find it very hard. She is a little old lady now, but still manipulative and still the same person in the end.

Maybe you can afford some therapy to work through your feelings. If not, maybe buy a self-help book...

I think when you're in a new relationship, your feelings, at the start, can be intense and laser-focused on that person and their history. If that history was bad, then you may have a strong emotional reaction to it, which may be out of proportion to what's 'currently' happening for that person.

It's not easy to deal with someone else's history of abuse or trauma because, in itself, it's upsetting anyway, but much much more so when it's about someone we love.