If you do have MSA I very much doubt you did this to yourself. No-one knows why people get MSA but it is my belief that history will prove that it is caused by a “wayward” gene.
Prognosis is generally believed to be between 7 and 12 years but can be less, can be more. The problem is knowing when it started.
I hope you are in a good support group – if not – please try and connect with one.