Redditor provides a succinct description of what will happen if OP allows his methhead sister to financially abuse him.

Come on, man. I was in a relationship with a girl for years and she was at various times physically, emotionally, and verbally abusive to me. She bled me dry financially over the course of years, and the second that she had to take more responsibility in our relationship, coincidentally also when my money entirely dried up, she left me in terrible fashion. I was left broke, emotionally scarred, and unable to trust again, and I later found out she lied to me about certain things, as well. Despite all of that, I loved her so much that I asked her to marry me, which thankfully didn't happen before she left me.

It wasn't because she was a girl, it was because she wasn't a great person. She was very mentally ill and had a bad upbringing. It's the same way as there being a great number of bad men out there. You can't hold it against a group of people like that just because you hear a story about an abusive guy. It would be easy for me to go "ALL WOMEN ARE EVIL!", but you know what? I hope I love again some day. Hopefully I've learned something and I fall for a better one next time.

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