Does She Really Hate Me? Breaks my Heart...

Basically me and my now ex-gf were going out for 4 months spring/summer and then about 2 months in the fall. After we broke up in the summer, we broke up a week after we both said we were in love with each other. After we broke up, the week after my ex started to get heavily addicted to a drug, then the end of summer she wanted me back and said she needed me in her life. As tough as it was, once she was basically almost off the drugs we said we loved each other again, but the same thing happened broke up/she started taking the drug again afterwards and when we break up she turns to a guy who is 10yrs older then her that is a drug dealer and gives her a major discount on the substance to keep her around. After we broke up she was yelling at me and name-calling, if I called a few times to see how she was. Recently I texted her to see how she was/miss her....she responded by taking me off her friends list online (petty) but never responded to the text. I did anything and everything for this girl, and never ever did her wrong except yell at her when we broke up telling her that she was wasting her life staying on the drugs and keeping in contact with that older guy.....does she really hate me? Do you think she took the drugs heavily both times because she really did love me and was scared of it/didnt know how to handle it? Any opinion is appreciated, thanks so much.

I think you're focusing on the wrong things at the moment. I know it's difficult...but - and i don't mean to be rude - you're making this about yourself when it shouldn't be.
Right now, you have 2 options:
1. Go to her and help her get out of her druggie funk
2. Let her live her life as she wants

(Translation: Either stick with her or move on with your life!)
Having said that, she doesn't really want you in her life right now...I don't know whether or not she hates you...but she doesn't seem to want your interference.

And finally, she's with the other guy because he's offering her a better deal: Discount for drugs. Then again, I don't know these people so maybe she does actually care for him.

If you really care that much about her, tell her you're there for her if she needs anything. But let her come to you. Other than that, I suggest you move on with your life.

If she's not willing to let you help her stop drugs, you need to give up everything with her.

As long as she has an addiction, she will be with that guy, regardless of his age, because of the great discount.

Edit: I do not believe she hates you, I think that she has an addiction problem and will do whatever possible to keep supplying that addiction.