It may be that, for the moment, he needs to be in total control and feeling responsible only for his own feelings whilst he comes to terms with how his MS is likely to impact on his role in relationships in the longer term. Perhaps he needs to be alone in order to think all that through.
Bear in mind that he will already have researched what MS might mean for him in years to come, and the fact that you have said it doesn’t bother you at all might come across as you sounding a little naive about it. He might therefore be reluctant to committ to you because he is scared to take the risk of loving you and losing you.
It would be a good idea to learn what you can about how MS can affect someone, so that you can show him you are thinking things through and deciding whether you are willing to travel that journey with him?
Having flare ups, or relapses, is awful. Everytime one happens you wonder whether what’s affected will be permanent. Whether there will be another one along soon. Whether it will force you to change the way you live your life.
Give him some time, learn what you can about MS, maybe back off from the romantic side of things and just be a friend for him.
I’ve been married 20 years and my husband finds it really hard to deal with sometimes - mostly because I find it hard to accept his help and feel like I’m not the wife he deserves! Sometimes, he just leaves me be for a day or two, and I come around in my own time when I feel ready to talk about things.
I hope it turns out well for you x