And I'm going to start right off with a teensy book list of romances featuring a disabled main character that I've read already:
Wolf Signs [link to page about book on author's website], by Vivian Arend, is a heterosexual paranormal romance. One might guess - correctly - from the title that it is about werewolves. The main female character in Wolf Signs is deaf.
One Dance With a Duke [link to page about book on author's website], by Tessa Dare, is a heterosexual historical romance (approximately Regency period). The titular duke pretty clearly has an anxiety disorder.
Three Nights With a Scoundrel [link to page about book on author's website], also by Tessa Dare, is the third book in the trilogy of which One Dance With a Duke is the first. The heroine in this heterosexual historical romance is deaf. There are some really interesting setting details related to that (for example, servants in her household use mirrors to make flashing lights to catch her attention, since she wouldn't be able to hear them knocking or speaking to her), though I have no idea how historically accurate they are.
I think an argument could be made that the male lead in the other book in the Stud Club trilogy, Twice Tempted by a Rogue [link to page about book on author's website], has PTSD, which might also be of interest to readers here.
ETA: I don't seem to be able to add new tags. I would suggest: romance, book lists, anxiety disorder