What do I do??? Please help me to understand depression!!

I meet my ex boyfriend 15 months ago and we fell in love so deeply and quick... we booked our first trip after two weeks. We have had an amazing relationship, we have been best friends, support each other, he is so sensitive and he showed me his emotions, etc. Before he meet me he used to talk with a girl online but she lives in another country, she helped him a lot when his dad was in hospital.

After 10 months, i found out they have been talking behind my back... my boyfriend said that she has been threating him to commit suicide if he doesn't talk to her...he has said so many things to her just to make her happy as he can't handle thay someone threat him with that. After a few days i decided to forgive him but after that he became depressed as he feels like he needed punishment. I think the girl is obssess with him as she has created a lots of fakes profiles just to talk to me or follow me to see my photos, she has rven applied to study in the same university as me. My ex boyfriend has told her not to come but she doesn't care... everytime he confront her, she makes him feel guilty. I think she's the problem as she has been manipulate him and playing with him.

I split with my ex boyfriend two months ago as i thought he didn't love me... then i realise that he was depressed. I tried to go back but he said he couldn't as he needs to be alone. We fought for two weeks and then wr became very close, he has been chasing me, we been out having dinner, we went to buy clothes, watched football together even when his parents were away he invited me over for three nights. Also two times that he has been drunk he has ended up in my door and saying I'm an angel for him. The last week around the 11th of december we started to talk so much and he opened so much about his issues, we talked for hours and hours. He decided he wanted me back so i said if he was sure.. he said yes. After that he came drunk late at night and saying so many cuite things to me, he said he loved me so much. Next day he was very down but i couldn't be with him as i was at work, next day he broke up with me and i felt devastated. I got so angry with him and said so many mean things that i didn't mean, I also said that he had hurt me a lot and said how he did it... after that day i apologize and he said he understood but now he doesn't want to have any contact with me... we stopped talking for a week and told him to meet me. He said that he had been out all week and it was good to see his friends after so long, he said he was going to start to go out more with them as he had fun, i was so happy with this statement. He also said he doesn't want to have contact because it hurts for him and i remind him that he is depressed and i think that's unfair as I'm thr only person that knows it, he presents to be okay with everybody else... so that hurt me. We were having the conversation in our special spot and he cried remembering memories of us... he said he will be fine as lone, he refused to see a doctor or therapist. He wants to be alone to deal with it but why he has cutt me off??

I don't understand why, I don't know if he really wants me out of his life o he doesn't want to hurt me anymore???? I'm devastated with this because i love him so much and i have been there for him. I understand that he needs space but I don't understand that one day he loved me and made plans with me to go in holiday and then next day he doesn't want to hear from me???

My head is a mess as i don't know what's best... I haven't talk to him