This is true. He can put more pressure on himself with his hand than you can with your girly parts. He needs to take a moratorium from masturbation to get his sensitivity back.

As far as affecting your sex life though, I'm not so sure about it. It almost sounds like there might be something else going on. It sounds like the masturbation is a reaction to stress to be perfectly honest.

The lowering of his sex drive isn't about you in any way, but possibly due to some depression or stress that he is alleviating through masturbation. Is there something else going on that's maybe money or work related?

Also, his "love language" might be related to your time together. When you're together more, his sex drive goes up and when you're apart more, it drops. This is the way I am. The more I feel like my wife and I are a couple, the more my sex drive goes up. When we are more distant, my sex drive drops.

But overall, it sounds like maybe there's something else going on.