My relationship with my girlfriend is at a stand still. What should I do.?

You have all the answers you need in your brief summary. If you don't find her attractive anymore, leave her. It stems beyond looks as well, it seems. You're not happy with her anymore, so why lead her on? Don't stay with her solely for not wanting to look like a selfish jerk. When in doubt, get out. It should feel appropriate, you should feel at ease. Not confused and flustered, like you said. I think you had your answer before you even asked.