That's so sad when it's one or both of your parents that stick it to you. It's actually because of my fond memories of my parents that I've bailed my sister out over & over again over the years for thousands of dollars. My dad was very frugal and taught me well about personal responsibility & personal financial management. My sister is 9 years younger than I, my mother gave birth to her in her late 40s, so my sister was their "miracle child", the daughter they always wanted, so so they spoiled her rotten. Instead of teaching my sister personal responsibility my dad bailed her out with money over & over. So when he passed away in 1988 my sister decided i was his replacement.
My sister has been in a lesbian relationship for over 12 years, and I don't care for her partner at all. I don't care about the gay thing, I'm very socially liberal, between two consenting adults, you do your thing and I'll do mine. I don't like her because she's so pushy and is one of those people that has to use the "f-word" as a substitute for every possible verb, noun, adverb & adjective.
So they realized it was too easy for me to say No! to the partner, so it became always my sister who asked me for money. In addition to being terrible at managing money, my sister is also a world class procrastinator, she always waits until a day or two before disaster is about to strike. Several years the mortgage company was days away from for foreclosing, so could I possibly please wire them $3500 today? I'm always leary of being duped by them, I called the mortgage company to verify, and then wire transferred the $$$. A couple of years ago it was property taxes, they said the Sheriff was coming the next day to nail an auction notice on their door. Their county allows online access to property tax records, so I could see they hadn't paid property taxes in 3 years! Another couple grand to bring them current. I told them it was the absolute last time I would help them out, but I always say that.
Why do I do it? I think of my mom & dad, how kind, wonderful & supportive they were to me, and I just can't allow their only daughter to become homeless.
This may sound harsh, but I'm going to say it...your sister has a life partner to help her out financially. She shouldn't have to rely on you. If she were in a relationship with a man, you'd expect that man to support your sister, not see her struggle, so I don't see the difference just because her partner happens to be a woman. Your sister is also GROWN. She is not a child. You acknowledge that she's a procrastinator but yet she continues to be "rewarded" (i.e. you bail her out) for her bad behavior. I can tell you're doing this out of love and responsibility, but how will she ever learn to be a self-sufficient adult if she knows she can just rely on you to take care of things for her. She is making her lack of planning and emergency for YOU...that's not fair! I'm not saying don't love your sister but I am saying that enabling her is not doing her any good. I was in a situation (see my earlier post) and it involved my parents...my PARENTS...those folks who are supposed to have MY back...I got taken advantage of repeatedly and until I said NO, I'm sure that would still be going on. Good luck to you and to your sister! Things always have a way of working out.