how to get my girl friend back

I’ve been in love with my ex for almost a year. At the beginning of the relationship, I have betrayed her, she have forgiven me. We do love each other deeply and stay together. We both have sacrified a lot. But during this few months, we often fight for what I’ve done in past. I suppose to tolerate but I have loss my temper on her for more than 6 times. I hurt myself, breaking thing and make her feel scared. She have warn me not to repeat it as she might run away some day. Last Sunday she did.She have left me. She think I cannot change my bad temper and doesn’t feel safe and secure with me. I don’t mean to scared or hurt her, every time she said want to break off or packing stuff to go away, I cannot control myself, I break thing. Start from the night she left me, I cry more than 10 hours a day when thinking of her. Not sleeping for more than 4 days and cannot eat well.Even sleeping pills doesn’t help. I’m thinking to suicide every time I think of her. Till this morning I’m still thinking to suicide, I CANNOT LIFE WITHOUT HER, I RATHER DIE THAN LIFE WITHOUT HER.

Hopefully you can help…