depression over breakup please read i need help

I'm 17 and I jus broke up with my first bf, well it was mutual. The relationship was goin great or at least I thought we started dating march 14, he had just broke up with his previous gf of a year and 2 months they even had a baby together. It was my first relationship so honestly I didn't know wat to do or how to b a great gf. When we first started dating he talked about her a lot how she was controlling and dirty and how he would never go back to her. He even honestly told me he still loved her though and that should have been a red flag right there but I was excited that someone actually liked me more than just a friend. I've always had self esteem problems I was never the popular one and skool never have had much friends and I would rather b around my family. But his ex kept harassing him and me she was the one who dumped him for another guy but she would call him saying how much she was sorry and that she wanted him back and she would break up with the kid she was with to b with him again he always refused or at least that's wat he told me. After we had been dating for 2 weeks he told me he slept wit his ex but is told me it was so that she would leave us alone and let him c the baby, the sad part is I told him was ok and I understood y he did it I didn't even get mad at him and I don't know y, I should have broken up wit him then that wasn't fair to me right. We had sex that night for the first time I was previously a virgin I guess I wanted to prove I was a good gf and everything was fine after that he didn't really do much after that and then a week and a half later he calls me telling me how much of jerk he is and I'm to nice of a person to do this to and he didn't want to break my heart I think he wanted to break up with me but he never said we agreed to talk the next day at his house after skool. We didn't really talk he just more or less told me that he had fallen out of love with me that he didn't feel the spark any more between us, he told me he talked to one of his girl friends and asked for her advice and she said just to give it time u never gave urself the time to get over ur other relationship first. I felt like I was being tested we had sex again that nite and I thought it was just him getting scared because it was close to our 1 month he seemed to go right back to the way he was before but after that the whole rest of the week I jus didn't feel like he wanted to b around me and I cried a lot we broke up that friday. Friday the 13 no less. It was a mutual break up he said he really did want to b friends with me still we Hung out the rest of the nite I was kinda tense cuz I didn't want to b all over him like I would hav if we were going out I thought I could do of but I came home and cried and jus when I thought I was getting better that Sunday I found out he was back with the baby momma like w peas in a pod like nothing ever happened. He told me the nite we broke up he never wanted her back and he was even in the process of getting custody of his son. I was happy for him and then that nite he is back with his ex she goes on his fb profile and starts harassing me saying I was never anything to him how I sucked in bed and I hav no Boobs and stuff like that how I was only I rebound which I know I was, but it still hurts. I miss him even though I shouldn't I cry all the time and tomorrow will b 2 weeks that we've been broken up and it sux Im jus gettin depressed over that fact I'm not good for anyone I was so happy with him. Before we started goin out I was slightly depressed and now its hitting me with full force and I don't know wat to do or how to get over this relationship. Please if u took the time to read this help me I don't know who to talk to and I don't want to go back and c a conselor.