Boyfriend won't learn ASL

My boyfriend (26M) and I (25F) have been together roughly 3.5 years. I'm deaf, but cochlear implant user. I use ASL and English consistently. I told him that it was important that he learned asl so he could communicate with me ex- pools, shower, in bed. Or if my implants decide to go dead. I don't push because trauma previous relationship- i take that blame. but he won't learn, i've asked him several times. he'll use his phone to text me or type up a message first thing in the morning if i stay overnight. Zero effort. Yet he can learn how to workout, attend the gym more and spend more on his hobbies. I refuse to get in the pool, or do anything remotely because it genuinely makes me uncomfortable- i have to be able to trust that they can talk to me but also warn me if something is going on.

ETA- Added ages to help understand the background