Maybe you should try to see how long you go without masturbation and see if that helps you achieve a stronger errection?

Yes it kindof help, try to stop masturbating for 2 - 3 days, you will see that you will get a much stronger erection when you masturbate again. However, I'm not sure how this would actually work with actual sex with a girl. I haven't tried it yet, but the last time I remember I did not have a good erection with the last girl I tried to sleep with, it could be from excessive masturbation daily, or i didn't like the girl nor the place nor the smell of her, could be anything. It happens sometimes. Sometimes it goes pretty well without any problems