@motoring,
Does she live near her family? How paralyzed is paralyzed? Is she currently in physio?
You don't say why you were thinking about ending things other than you were growing apart. Could you live with her the way things are? How easily could you live without her?
Have you discussed this with her? You've got some thinking and decision-making to do.
FWIW: I don't believe anyone should dedicate their life to someone they don't love or that they should stay out of guilt or obligation. That's just going to mess up both lives and would be like living a life sentence. I also don't think you're responsible for the accident. That's why they're called 'accidents'.
I hope you guys can talk this through so you're both okay.
Edit: Oh, and I'm very, very sorry this happened to her.