My relationship is suffering because of depression. Can someone please help me!?

I'm so sorry to hear how low you have been feeling.Sometimes we think we are the only ones going through a tough time, but try to remember depression and sadness are part of the human condition. Your past is something that happened to you and not who you are, remembering this really helps as sometimes we identify with the past too much. Try and use your experience to help others. Is there any way you can do some volunteer work related to people overcoming drug use? Be thankful for what you do have, your health, your girlfriend, focus on the good things.The past is gone and we can't change it . We can only live in the present moment.