I am so sorry you have to deal with someone so inconsiderate. I have a brother with disabilities as well, he is non-verbal and literally a 23 year old that looks like a 10 year old and acts like a infant. I have slept with him multiple times while my parents were on trips or events, and he is like a little baby that has to be taken care of, so if your bf thinks anything beyond that, that just blows my mind away. it could be anyone? what if it was him or someone he cared for ? would he not want his loved ones to take care of him?

All I can offer is virtual hugs, and maybe educate him and has he met your brother? maybe when he sees him, he might think differently.