Gf pregnant but cant get over my ex?

honstly I would just tell the truth. As hard as it is, you will be happier in the end. You are hurting yourself with all the guilt you are carrying with you. If you dont love this new girl, you should not be with her. Try talking to the other one, and work things out. Also if you go to aa meetings, maybe you can see your daughter unsupervised once you prove you are done with drinking and drugs. A child is more important than any drug. Good luck hope it works out in the end, everything always works itself out