When I was with XP (DS' Dad) - he was emotionally abusive, I generally wasn't happy at all, one of the biggest things for me was a total lack of non-sexual affection. - I used to dream about my ex before him, who was a bit of an arsehole, but was very affectionate and loving. It was weird, these dreams were really vivid. I know he has a son slightly older than my DS, but I have never met him, and in the dreams I would bump into ex-bf and we'd meet up and take our children to the park and I'd offload about my XP to him and he would sympathise and give me a hug, but nothing more. Which was odd in itself because in RL when I broke up with him, I had to go cold turkey on seeing him because I found him too attractive to resist
Anyway I had a couple of dreams like this a few months apart, and would wake up feeling slightly guilty but also comforted. Once I had made the decision to leave XP, the dreams came back, but they had stepped up a level. I would dream I was going to his house in the middle of the night or something and I may have kissed him in one of the dreams, I can't remember. I just remember him holding me and telling me it would be alright.
Some time after I had left XP, I had one final dream about him. I dreamt that I went to his house, thinking "Hey, I'm single now - I can do what I want with him this time" but then when I was there, I was talking to him for a bit, and then I just suddenly realised that I felt really apathetic about him, like all my feelings for him had gone. And I didn't shag him, even though I had planned to (in the dream).
It was odd, I almost feel on some level he helped me leave, but of course it couldn't be him. I don't think he has died or anything I suppose maybe it was just something within me that appeared as him just to give it some kind of form.
Oh and the weirdest part is, when I was with XP, if I came across a picture or mention of ex-bf unexpectedly, it made me feel all weird, but now if I see a picture it's like seeing any old friend - there are no feelings there at all.