I feel severely depressed someone please help

I don’t know what to do anymore. My life feels like it’s going no where. I was in a relationship for 6 years. We lived together and I had no choice but to end it as he was an alcoholic, emotionally abusive but sweet at the same time, he hurt me so many times, I love him so much and it pains me to think of him with another girl. I gave him everything. I’m so broken and feel like I’ll never recover. On top of that my best friend hasnt been supportive during this time. She is always in and off and it’s super selfish especially during this time. I don’t have a lot of friends because for the last 6 years I spent it with my boyfriend which now leaves me very lonely and depressed. I have a job that I hate and I never seem to be able to just be happy. I don’t know how people are supposed to recover from this. It’s so traumatic. I love my ex boyfriend and it’s so hard when it feels like he was the only person for me there when no one was. How am I supposed to be happy again. I seriously need help. Please.