I think I accidentally SA'd a girl

For context I (19M) and this girl (19F) started going out when we met in an introductory course in college for a little over a month before she ditched me and went back to her ex.

About 4 months later she texts me out of the blue saying she made the wrong choice, that she regrets it and misses me a lot. And so I went to her house fully intending to finally get a cleab cut from what we were or could've been, but in that moment all those feelings ive gotten over came rushing back (stupid, i know) and we ended up meting a couple more times in some friendly-flirty sentimental talks where she basically ended things with me again for mental health reasons.

Fast forward a couple more weeks and she AGAIN texts me out of basically saying she wanted me to take her first time before we actually stop talking for good. I agreed because I also had the hots for her.

And so we met up (twice, on different days), the deed was done and it was awesome, wholesome and nice, that second night she actually blocked cause she said she wouldnt be able to keep herself from texting me again.

Fast forward about two weeks to yesterday and I see her at a party. I don't want to talk to her because it would be awkward and sad for me, but once I get some drinks going I see her and I go say hi. We are chatting normally and I notice her friends keeping watch on her so she doesn't do anything stupid. And it happens, I kiss her.

Everything was so sudden, I dont know why I did this, suddenly all her friends take her away and separate us at which point I find out she probably has a boyfriend (Ouch, so that tells me she didn't want me) and I immediatly realize the massive mistake I had just made. I never thought I would be THAT guy. I see she is smiling but even so.

I immediatly left the party and texted her on every platform im not blocked on to apologize. I sent paragraph after paragraph after paragraph telling her im sorry for kissing her.

Im not able to get awink of sleep until she texts back. She tells me she doesn't remember what happened even though it had only been about two hours, I don't believe her because we weren't that hammered to get blackout that instant so I think she is trying to spare me some dignity.

Next day once im completely sobered up I again apologized profusely via text. We talk, briefly her saying she doesn't remember anything and me explaining everything that happened. She ultimately forgives me and tells me not to worry about it.

Even so it's been eating at me and I feel horrible for what I did, there's nothing I hate more that douches that don't care about consent.

I would like to blame it on the fact that we both were wasted but I have to accept my mistake.

Am I a bad person? she tells me im good and that I was always very respectful to her while we were going out but even still the guilt won't go away.

What is the next step? forgiving myself?

Anyway I just needed to rant.

TL;DR: I stole a kiss and it's been eating at me all day.