I think women care not so much about what disease you have got but about your attitude to caring for yourself, managing your disease etc.
If a woman can see that you don't care for yourself, that you skip injections or that you aren't comfortable with your own disease, then it may well be that at some subconscious level you indicate to her that you won't be an easy person to settle down with. It might suggest to her that you are looking for a 'mother-figure' to care for you rather than an equal partner.
Anecdotally, my brother is Type 1, he looks after himself, exercises a lot, doesn't eat junk food, doesn't smoke or drink and injects when he should. He has landed a kind, stunning, smart, cultured and loaded woman. She doesn't have a problem with my brother's diabetes.
My dad is on insulin for Type 2, he doesn't take care of himself, eats junkfood and loads of carbs, misses injections, doesn't self-test, rarely exercises, doesn't want to learn about diabetes and sticks his head in the sand (in spite of ready access to my copy of Dr Bernstein). My mum sticks with him because she loves him but if she'd known 30 years before that that's how he'd approach his future disease, I'm not sure that she'd have been so attracted to him in the first place.
WRT to the ED issue, I can understand that from a man's perspective ED must be soul destroying. But from a woman's perspective it is worth bearing in mind that their are plenty of ways to please your woman that don't involve your penis (worth studying up on this for the many intervening years before you get ED!!)