I'm really sorry about your gf and son. Is there any way to negotiate with your gf to get her back? Communication is always the key to getting what you need. Maybe make a plan to get sober and once you are stable enough to be persuasive, ask her to come home. Make promises you can keep, and keep them. Also, perhaps tell your mom that the woman and child are YOUR family and belong with you. Tell her your son needs a father and she needs to seek help with her alcoholism so your family doesn't have to pick up her slack. Make changes in your life that keep people close rather than push them away. Use this forum for support and keep in touch
^ beautiful post and great advice. I think that in every tough situation in life it is always important to see what you can change. We spend a lot of time focusing on what other people need to change (in our minds) but that actually works against us. In this situation, OP, you can focus on getting sober so that you are in control of your life. That will put you in a much better position to regain a close relationship with your son. It is next to impossible to get and stay sober without support. Make a plan for something that will work for you, someplace that you feel comfortable but challenged. Good luck and let us know how it's going when you can.