Whats wrong with my friend?

I remember when i gain weight she use to say "OMG you have got so big blah blah blah" But now that she gains weight and i lost a lot i don't throw it up in her face. She talk to one of her friends boyfriend and use the excuse she is grown and she doesn't have to tell her friend because its not her business she try to justified everything she does wrong. If she does not have a dime or a jug of juice i will come through for her but when i was a dollar short on some medicine she would not give me a dollar. If im on the phone are having fun she will talk really loud are sing really loud to get my attention. She always mention my ex boyfriend name around me like she likes him. She never talks about anything positive unless its or about drama. I remember one day i was having a bad hair day and she pull of my hoodie and smiled. She seems to like every guy i like & says she can get any guy she wants.She scared to go places by herself, She always want to play fight with me everytime im around i think she is sick in the head. She always saying how sad she is about her life & things never turn out her way but its the way she treat others. Does that make her feel better about herself?