I haven't told anyone in rl about this.
About 5 years before dh and I were married, we had a really rocky patch and I was unfaithful to him with a colleague. I was in my early 20s, the om about 10 years older with a dw and young children. It was a horrible infatuation type thing. We slept together, and it was emotional as well as physical. It lasted a few months.
I instigated a break from my then dbf and this gave me a bit of space and clarity to see that I didn't want to be with om at all in any sense. Om was talking about leaving his dw, I definitely didn't want that and either way I suddenly saw him properly for the first time for who he really was. I ended all contact with om, and I'd changed jobs by then so it was a clean break. It was as if a cloud had lifted and I realized again that my dbf was of course the man I loved and wanted to be with. It was horribly selfish, I know. Dbf and I got back together and that was that.
I've never told dh about it. Om has never told dh, and definitely wouldn't, I think because a) he's not that much of an ass (despite the affair, obviously) but also b) I guess I could do the same to his dp and then everyone would be in the shit. It's not a risk on either side but I mention it so as not to drip feed.
I've been completely faithful to dh, up to our wedding and ever since, and plan never to tell him. Dh and I have been happily married just over 10 years now.
I think about it very rarely and when I do it's in a shameful way, regretting it all but knowing it was a lifetime ago and before we made our vows.
The issue is that recently the om has been in my dreams, as if we're still having an affair, and it's awful. Is this my shame and guilt making itself known? Would a counsellor help? I know it's awful what I've done and I'll never know if dh would have stuck with me if I'd told him at the time.
Any words of advice would be helpful. Thanks