dating someone with MD

hi, i’m a 27yo female dating a 27yo male with MD & he’s not very forthcoming about it nor has he ever felt really comfortable talking about it… he tells me that he doesn’t know what type he has but i believe it’s DMD since his mother has posted about DMD awareness day. his brother has MD too & i’m not sure if they would automatically have the same kind. I’m very anxious about his life expectancy and how his body might change. if i google life expectancy it’ll say 20s-30s. he was diagnosed as a child. is that realistic? is there any hope of a cure in the future? would love any feedback or experience one might have. I don’t know how or if it’s unfair to try and bring these conversations up especially when he wants to avoid talking about it, very understandably so. i do want kids one day and he’s open to it too. thank you so much