Maybe you're going for the wrong sort of woman and also going about things the wrong way.
Try to go for flat-chested or hairy girls who won't have an inflated idea of their own importance.
Forget the champagne and develop a relationship.
Sex is best in a permanent relationship and in that context, as long as your penis is long enough to couple, its size will be relatively unimportant. You don't actually say how long it is, erect.