Crying during positive/negative nostalgia, watching old vids

Not sure what possessed me to re-watch some old recordings from when I was 3, but I can't believe how easily I broke down... seeing this tiny guy, with apparent happiness that is now unknown to me, widely smiling (not at 12, then... every single picture I'm in I just don't smile at all, even when I, for some reason, have silly costumes on)... and in the background, this (now I noticed) mobster-like (due to sunglasses inside, no idea if that's the impression he was going for) mother****er whose apparent hobby was using me worse than others use punching bags, mostly randomly ( justpaste.it/depressedanger )... oh, in the video it's all fine and dandy (he was even singing 'happy birthday', and moving some balloons around... like, what)... but in the same very room, just when all the aunts and uncles were out of the picture, he worked so ******* hard to beat that smile off my face... and decades later I can barely watch these without resorting to alcohol... funny thing, considering he's such a tiny, happy fellow in the video... if only I didn't know what followed, for 18 whole years, all with the nation's approval... it's not like I watch them often, at all, and in fact nostalgia, somehow, for me is more often positive, because in some weird way I don't really understand I was able to enjoy rpgs back then, so remembering them (which is easy, through music, or... playing, but he really managed to destroy that ability of mine)... is positive... but sometimes I worry I might end up conflating both events in my mind, since there was often so little time in between, and then the positivity would obviously be gone, too, and all of my initial 15 years (couldn't play the last 3, just as I barely do now)... would be is a train of grim, miserable pain...

I can definitely identify with you since I suspect our childhood's had many sad parallels. Photos from my youth remind me of so many bad things that happened to me. I am often crying in the photos. Wish I knew what to say to help you.