What can i do to stop this anger?

Hey great people,ive split with my ex quite a while now+ive meet someone new.Its been six months but i still think of her+somedays it gets me so down!Anyways she told me she had fell outta love for me,but i didnt do anything wrong,i couldnt understand it because i was there for her 24/7 for all her needs and wants.I had to get up and leave(after 2 years living 2gether)!Had to change my whole lifestyle leave everything i had put into it,and all the love i had given her2 it killed me.I think ive got past the ruff times afterwards but sometimes when im drunk i text,or ring her and give nasty msgs and can barely mind what i sent or texted,i dont understand this because im really not a angry person+wouldnt hurt a fly but ive done this twice now!!I care for her allot+want her to speak to me again because we shared so much 2gether and i really want to be mates in the future.What can i do to get rid of this anger and just be me again?