I dont think your mom could have contracted HCV from her husband because he cheated on her....something else maybe, but not HCV. Its true that sharing razors is a way to transmit HCV but your mom would have to be infected with it. If you think your mom may have it, ask her. If this still doesn't put your mind at ease then get tested.
Good luck
Could I have gotten it?
___________
"If" your mother has hepatitis C you could be at risk by using her razor. If you are concerned get tested and ask your mother to get tested. Everyone should be tested at least once in their life. This might be a good time to get that test. it would be in your best interest to keep your personal items for your personal use only. Razors, tooth brushes, nail clippers etc. all have possibility of passing blood if used by someone else. Again, if you concerned that you may have been exposed to Hepatitis C.....GET TESTED! It's the only way you will know for sure.