ADVICE PLEASE 😭😭😭

I'm 15 years old. I went to my moms the other day, which I don't do often at all, and asked her if she wanted to go out to eat. She said sure. She then invited my step brothers. We went to my Nannys office (that's who I stay with) and she got $20 from her. I had my own money because I needed to stop at Walmart which is right by the restaurant we were going to and pick some things up. When we got done eating my mom took my money and paid for EVERYONE even though she took $20 from my nanny. I would've already had to pay for myself. So instead of spender $10 on myself, I had to buy everyones food! Then I didn't get to buy my groceries! My moms ALWAYS borrowing money from me, doesn't call me unless she needs something. She walked out on me and moved in with a guy who does drugs, doesn't have a job, she knowingly lets him cheat on her, she started drinking, started smoking, she lost her job, she lost the house she owned and I had to move into an apartment with my nanny. Before she was a dentist, worked out every day, cooked dinner, spent all the time she could with me, took me places, did anything and everything for me. And my world has completely fallen apart because of it. She's not my mother anymore. I've tried talking to her. I poured my heart out to her and all she said was "sorry you feel that way" then I kept on and she ignored me until she finally said to leave her alone because she didn't wanna be bothered anymore. When people ask about me I'm just her friend and her boyfriends kids are her sons. I already don't have a father, I never have. But after last week when she did me dirty like that and then has ignored all my calls and texts since I don't know what to do anymore. She won't give custody to my nanny and I don't know Kentucky's laws for 15 year olds. I don't know what to tell my mom. I was extremely suicidal and I'm finally better now, but she quit taking me to therapy because they started charging her. I just don't know what to do anymore, I need advice. Someone please help.