I live about an hour and a half from my parents. I did live a little over two hours away for several years. Where we live is perfect. Go north an hour and a half and you're at my parents, go south the same distance and you're at Bruce's moms.
My sister lives over 8 hours away. But my parents have always been very supportive of what we choose to do in our lives. My brother and his family live right next door to my parents, so they always have family very close by. I go visit often and my sister comes down when she can.

Don't let your mom influence your decision too much. She might not like the arrangements at first, but you will all adjust after a while. Personally I think it might make the relationship even stronger. You'll cherish time spent together even more. Like Karen said, let her know you still love her. Moving away doesn't change that. Make plans to talk on the phone on a regular schedule. I talk to my mom on my way home from work twice a week (it was everyday but I run out of minutes on my phone, so we had to cut it down to twice a week). She even started watching some of the shows I watch so we have things to talk about.