His Sexual Confidence Lack

I love the way my SO and I make love. The emotional and physical connections are all I need, and i feel so loved. Unfortunately it takes a lot of soothing and foreplay to get him excited, and then it doesn't last long. And this is what he worries about : that he can't last long or satisfy me. He has been tested and found he has low T. Done viagra. When he's drunk he performs very well , nothing like when he's sober which makes me think this is all about his confidence. How do I reassure my babe I'm happy with our sexual relationship? That he doesn't have to drink to make great love?