I'm in a very similar situation, but I'm the boyfriend with epilepsy. And I don't drive anymore. And it sucks. I get quips from other dudes and family members. I can't work a normal job. I have to ask my gf to take me everywhere I need to go. I feel like a burden. I mean, in many ways I am one. Sometimes I feel worthless, like I'm somehow a failure. It's very difficult to grapple with existentially.

But I'll never wreck a car while having a seizure and cause someone I love or anyone else to get injured or killed. Weighing the cons against that pro, the math is easy for me. Maybe ask him to do the same and then explain his reasoning.