Need advice asap I got my girlfriend sister pregnant what should I do?

Anonymous
Am looking for real advice so trolls stay away. Pretty much my girlfriend asked me and her sister to spend a day together to try making amends with each other so for her sake we argeed. I say this now i really dislike her older sister becuase she told her family a lot things about me that just wasn't true. All I will say is because of her lies something really horrible happened to my girlfriend that I just can't forgiven her for long story. The only reason I argee to even spend any time at all with my girlfriend family is for her... she hasn't spoke too her family in two years after the mess her sister cause so I just wanted her to be happy. I'll keep this short so the story doesn't go on forever if you want details just ask.

So pretty much me and my girlfriend older sister got shit face drunk and had sex. the next day I wake up in another room not remembering a thing. i did asked my girlfriend sisters what happened she lied and said nothing happened i just kept falling over made a joke about me being a light weight and said she just put me to sleep so I don't hurt myself. 3 weeks later I get a Facebook message from her saying she pregnant and it's mine wants to keep it and is unsure what to do. I didn't take her seriously as first at all since I wouldn't ever cheat on my girlfriend let alone with someone a hate so much I wanna kill. So I played along asked a few questions I started remembering bits and pieces as she told the story. after I realize she wasn't lying I told her we need to tell my girlfriend asap together now but I'll give a week to think on it. What makes this worse is the fact I already have a kid with my girlfriend she's 12 months now am having one with her sister I regret... Drinking to make my girlfriend sister family happy and the fact i got so drunk I didn't even remember having sex with the girl till now. I only this was the first time I ever drink anything in my life and this happens this is why people shouldn't drink.
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+1 y
already known the right thing to do but am going fucking crazy... and no matter what her sister says am telling my girlfriend. The problem is am unsure how things will change from her since I now will have two girls with my girlfriend and her sisters. So what her sister now gonna be my baby mom? Her parents already hate me from lies her sister told this will just make shit worse. All I known is I wanna rasie my kids in one house not two but this is just so fucked up.. all from drinking and trying to be nice.
Need advice asap I got my girlfriend sister pregnant what should I do?
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