My sister's sex drive is ruining my life, but she's an angel!? iin?

My sister's sex drive is making my life miserable.

I work almost 60 hours a week and I am taking classes to try to finish a degree I started 4 years ago. I rent a small apartment and my life was pretty stressful but I could handle it.

My sister, however, is a huge... slut! She was living with some room mates and had a part time job paying the rent and when she wasn't at work, eating or sleeping she was in some other man's bed. She REFUSES to get a prescription for The Pill ("I don't want to lose my figure, it makes girls gain weight and causes heart attacks!") and I know from listening to her when she gets drunk with friends that she uses condoms, but when they are unavailable she relies on... chance.

Chance failed her 3 years ago when she had her first baby. She lost her job because she didn't qualify for maternity leave so she had to move in with me. My life has been very difficult ever since. She still lives her lifestyle and I have had to kick many a men out of my apartment. She has become SOMEWHAT more responsible, but I still come home to a VERY messy and stinky apartment and a sister, sitting on the couch, watching TV and telling me that I need to be more tolerant because I don't know how hard motherhood is.

I woke up to her crying baby constantly, I had to give up just about every bit of living space I had to her and the kid and she doesn't work, she collects benefits from the government but she refuses to pay rent. Often times I find myself having to care for the child for her while she leaves to go out to party and I've had it. I've had it with having to give her money and pay for a kid that isn't mind. Just had it.

I can't complain about this to anyone that knows her and most people that I know know HER. According to them, I am being selfish, uncharitable, that I have NO idea how hard it is to be a single Mom. You know what upsets me the most? She is pregnant AGAIN! Yet I am the selfish one! She has one baby that is depending on ME for food, clothing and shelter and she couldn't keep herself from having another!?

I don't feel like the selfish one, SHE IS THE SELFISH ONE for having another baby when we can't afford THIS ONE! I can't kick out my own nephew and SHE KNOWS THIS! I have had to go on anxiety pills to tolerate all of this, her friends being over, my apartment looking like shit, and now she is pregnant again. The worst part is, I'm not even telling half the story.

Am I selfish? Is it normal to have your life screwed up like this for someone else's mistakes? Is it normal that someone so fucked up is seen as such an angel!?