Hi Weekend,
One of the things that will help for this weekend at least is to have a plan of alternative things to do. Maybe take the girlfriend out to a nice dinner, a movie, or out in the country/to the park? Maybe there's something to do around the house? Or a hobby or sport that you can partake in?
It's great that you're on here-- we are a very friendly and supportive bunch. Do you have support in the offline world as well? Have you told your girlfriend, a friend or a family member about what you're trying to accomplish? Have you considered meetings?
You sound very together... I think you can do this. Keep posting and reading here on SR -- it's a great resource and source of inspiration.