A lot of guys seem to have this problem. It's all in your head. My suggestions is, get a box of cheap condoms and try using them when you are home alone masturbating. Get used to puting them on and keeping them on during sexual contact. Then have your girl gradually get in on the action. Have her jerk you off with one on. See if this gradual introduction to condoms helps you out. You are probably just nervous since it it your first time. I think you just need to be more comfortable in your own skin. If you don't want to do that, try taking a bubble bath with her. Fool around in the tub a little and then get out, dry each other off and lay down with her in the warm blankets and try it then. You will be all relaxed after the bath and this might help. It's all in your head which means you can talk yourself out of anything you want to. Just try not to stress about it or think about it too much when you are doing it. Focus on how beautiful she is and how much you love her, not on your penis. If you focus too much on it, you are bound to go soft from all that stress and pressure.

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