How to forgive rude people?

People who make rude jokes after knowing you for literally 2 minutes, like telling my boyfriend it’s never too late to sleep around (while I was standing next to him) and asking if my mom’s a drug addict because she’s an artist. They say it’s humor, I say it’s classless.

I was raised in a loving environment with solid values, I went to private school and university and all that crap. And while I have that in my toolbelt to ground myself, it still hurt and I can’t get over it.

Although I’m proud of myself for refusing to compromise my values and stoop to their level, I still feel like I should’ve fought back. Then again I’m pretty sure that’s just the anger talking, so all I really have left is to forgive them… but I can’t.

Any tips on how to do it and what I can do if it happens again in the future? Thank you in advance