So, trying to make a long story short. I have a best friend that I have had for 25 years now. We have been inseparable from about 2 years old until about 24, but in the last few years she has become rather absent. She had a lot of things go wrong in her life lately so I have tried to understand, but she just becomes less and less of a friend. As soon as I got engaged last December I asked her to be my maid of honor because that's what we thought we would always be to each other. She has not been much of a help and she has been absent from my last two birthday parties, my daughter's birthday party, and constantly ditches on plans. Every time I get upset and we have a discussion about whether to even be friends anymore because it is getting to be too much for me when I am always there for her but she doesn't return the favor. The last argument was when she completely ditched me for my birthday again and I told her I could no longer be friends with her because she is never there for me and ditches me all the time. She is now begging to be friends again like usual and finally apologizing after attacking me for having an easier life than her, even though I have worked my ass off for everything I have. We have had the discussion about her not being my maid of honor anymore but every time she apologizes she expects to be let back into the position, even though I have another best friend that is there for me for everything and has done way more to help me plan this wedding. This time after I forgive her she texts with "When do I need to have my bridesmaid dress money?" like her ditching me didn't affect anything again. I don't know what to do and how to explain to her that she definitely isn't my maid of honor and possibly not even in the wedding anymore. I don't want to come off as a mean, snarky bride, but this is a friend I have been there for through everything and have been let down by someone I thought of as a sister one too many times. I have so many people in my life that don't like her so it is hard to ask for advice from them without them already having an opinion.