How am I vulnerable as a disabled person in my home?

Vulnerable to ?? What? Falls? Injury? Infectious disease? Crime? Probably yes, but with precautions and appropriate assistance there is no reason that you can't be safe healthy and happy on your home. .
Depends. It depends on your living situation and the type of your disability. If you have a lot of physical impairment, then you are vulnerable in that you are very prone to injuries and accidents unless you have reliable help from outside. If you live with someone who doesn't care or is abusive, you may become a victim of his/her abuse, both physical and/or emotional.