Sick of being depressed and having a social phobia?

Nothing ever seems to change with me. I apologize in advance but I need to vent and I can't talk to anyone about this so I figured I would get some strangers opinions of what I should do. I have worked at the same job for ten years. I am having a affair with my boss for two years. We talk about marriage, kids, etc. but he drinks alot and I wonder if anything will ever come of it. I am shy and don't have many friends, and my anxiety is overtaking me because I'm scared it will not work out. If it doesn't will I lose my job? I have a seventeen year old daughter that is hard enough to deal with. I spend my night mostly at home popping pain killers to ease my worry and pain. I am a good mother and had to raise my daughter myself. Now that she is almost grown I fear I will be lonely and never married. I know I have issues. Just venting and thanks for reading.