Naturally, it would be very uncomfortable to get married if either of your parents are not happy with your decision. I’m assuming that your mother is the “unhappy” one here? Have you tried listening to/reflecting over your mother’s concerns? Perhaps they are are valid. What about your dad and the rest of your family? How do they feel about the guy? If your dad is okay with it, maybe he can try to reassure your mom. Or maybe you guys all need to sit down and calmly talk this out (all the pros and cons…because it is a huge and life altering decision after all).