My BF stopped watching porn and now sex with him is horrible

My BF (38M) was single for a few years before we started dating and he told me that he would masturbate while watching porn every night when he was single. For the first year of our relationship, our sex was incredible, he could last forever and could have sex 3 times a day if he wanted to.

A year into our relationship, he decided to stop watching porn and omg.... The sex with him went from 100 to pretty much 0. He can only last like 5 minutes before he comes and only wants sex once every other day. I had no idea porn was affecting his libido that much but apparently it was.

Men of Reddit, have any of you experienced this? How long is the adjustment going to take? Is there anything I can do to help him last longer?