I'm going to come out to my girlfriend
Why do you want to do that?
I am living a lie being with her.
You should be honest with your partner. That's a tough situation but telling the truth will make it easier.
The truth is hard. I can't handle the truth. It's too much to handle.
Your girlfriend will help you handle the truth. If you trust her enough to date her, you can also come out to her, even if it means the end of the relationship. She will support you.