It’s my fault...?

So I came across the text messages, the dick appointment is being planned, I throw away his condoms thinking that’s gonna stop him from having sex with her. But no. They end up doing it anyways, and the story I got was that she was riding him and didn’t get off. 🤦🏽‍♀️ typical huh? The next day, after their little whatever, she told him that she was otw to get plan b from Walgreens. I’m thinking “SMART BITCH, YOU BETTER GO GET IT” but noooooo, DAYSSS after she text him saying “you know I didn’t get no plan b right?” And now the bitch is “pregnant” for my boyfriend of 2 years. She’s 21, has 4 kids already, works security and “hustles”. Im not sure if they all have the same father but she has a boyfriend in jail and I’m aware of “A” baby daddy helping her. I’m 18 and he’s 19. He told me everything after she told him she was pregnant. He said, she was just “a nut”. That he doesn’t want this baby with her but his dad wasn’t in his life and he hates that fact and can’t do that if she decides to keep it. She’s been over at the house before, he disrespected me infront of her and everytime she leaves she texts him saying “I felt something more for u today” and IT HUURRTTTSSS. But throughout all that one night he came home drunk and apologized, saying he don’t wanna lose me, I’m his wife, and all that crap, but he disrespected me infront of her and got her feeling superior, and that I’m not shit, and he’ll leave me for her. I guess that’s why she didn’t get the plan b, she wanted my man and thinks a baby will take him from me. He hasn’t been talking to her for a few days, she says that she feels as if she’s gonna be a single parent. All I did was laugh when I read the message 😂 I told her not to cancel her abortion, she sent him a screenshot of her appointment and all, I gave her reasons, I told her he wasn’t serious about her. I told her the things he told me. And now she’s just scared she gonna be a single parent, I mean you already are. Tbh, I’m not trynna be mean or rude or anything but I feel as if she did all 4 to herself trying to keep whoever she was with at the time.

The whole point to this long post is, should I leave? I wanted to be the first, to have the first. And not being that over a stupid mistake. If I didn’t throw his condoms away it wouldn’t have happened. If he didn’t want to be a hoe, it wouldn’t have happened. He doesn’t want me to and I don’t either but not being the first to give you your first, hurts. Especially when you actually love me and not her.