As someone who is 41 and has just learned ways to work around it, if you keep bringing it up and making him feel pressured (which I don't know if you are), but just saying that could cause one to feel backed into a corner, more than they already feel. My wife doesn't bring it up except if I talk about it. The only other therapy I thought about trying was hypnotherapy. But there came a point in my life where I accepted it won't go away but just had to live with the fact that certain tactics I can ise depending on the situation to hide it the best I could.