Feeling so down

i have been with my SO for 3 years and he cheated on me a few times when we hit the 1year and a half mark he has he was addicted to different women he did take a lot of pills like adderall and a Zanex i think that’s how you spell it plus he was a heavy alcoholic he used to be so violent and get so angry fast he just wasn’t himself when i first met him he didn’t take pills and he didn’t drink as much. and half the shit he didn’t even remember doing and would always say that i was lying or he didn’t remember doing that a bunch of times he would be so ducked up he would be passed out in his car wake up and not even know where he was. anyways i got pregnant and he was doing better then started to fuck escorts and when i found out i told him this was my last straw fast forward to now and he’s better he hasn’t cheated on me or anything and he’s gotten help he stopped drinking and taking pills and our relationship is so much better i know that i decided to forgive him and some years has passed but i cant shake looking up the girls he cheated on me with and i get so depressed when i think about it 😢 sorry i just wanted to vent