I (20m) had a talk with my mom (69f) and my dad (65m) and now my confidence is ruined and my trust in them and my brother are ruined, what do i do now?

so recently i (20m) did the dumbest thing i could do and go to talk with my parents about some insecurities that ive been having. during this conversation my brother who is 10 years older than me came up and specifically his love life and my parents previous love life. turns out my brother was dating four women at the same time at one point for almost two years this didn't sit right with me and i made it known, my parenst seemed to shrug it off as if it were nothing(or at least thats how i interpereted their dismissal of my feelings on the matter). they then told me that they did similar things when they were younger, my mom admitted that at one point she had multiple boyfriends, one for sex, another for money and a third for love, and my dad also admitted to being the other man in several instances,one even resulting with my oldest sister being born, before meeting my mom when i was born.

this has caused me to feel very insecure and disgusted with my whole family. the casualness in which they admitted this and the seeming lack of remorse makes me angry and hurt because it means that those reddit stories about scumbag men and women are true and my parents are among them. they didnt raise me like that, they raised me to be better but now it feels like they were faking it and inhibiting me in some way, like keeping me at home as much as possible to prevent me from developing proper social skills.

i dont know if this is just me projecting, being shell shocked at a revalation or just my own worries being confirmed but i feel like i cant trust them or my brother anymore and im starting to feel alot of anger at my upbringing. please can anyone weigh in? i dont want to feel this way please.