You should know about his beliefs, now most Shia members have kufr beliefs. Most of them has this "Quran has changed" belief, Astagfirulloh. Ask him, if he also has this belief, then you can not marry to him.
If he is in Imamiy or Ja'fariy mazhab then you can marry to him.
According to Hadith, the Messenger (p.b.u.h) admonishes us to respect the disabled and to be helpful.
There is nothing said about disabled grooms or brides. If a woman freely decides to be your wife, she will do it for your qualities and she will know that she will have to live with the obstacles linked to your disability, and maybe she likes to be helpful.
First of all, the risk of having such diseases is much reduced if a couple is having intercourse only with each other rather than with different people.
Secondly, It is Allah who has ordered us to get married in order to have intercourse. There is no questioning to Allah's orders. Most of the things that Allah has ordered have their answers in Quran and ...