His and Her Health

Several months ago I had absoulty no sex drive at all. After getting off the pill, and getting through some emotional issues, my sex drive thankfully has been restored. However, now, my husband seems to be having difficulty. He says that the desire is still there, as well as the fantasies, but he is having trouble maintaing an erection. When this first happened, I thought it was me, but when we talked about it, he said that it wasn't, that he even had problems if he was "taking matters into his own hands." My question is, does anyone have any idea what could be going on. I had NO desire, fantasies, or thoughts about sex when I was having difficulity. He however, is having all of that, just having difficulity physically responding. He had a vascectomey about 8 months ago, and we don't know if that could have something to do with it. Any help or sugguestions would be appreciated. Thanks in advance !!