Will I Ever Change My Ways?

i love my family to death but i seem to keep snapping at them. there is a lot to it but i will not put my whole life on the internet. basically i am in college majoring in biology pre-med. but i ask myself, how can i be a doctor and help people if i can't even treat my family right or love myself right? don't get me wrong, i absolutely LOVE helping, caring, advising for people... but it is strange because i am more friendly to strangers than my own family. and to make things more sad, i am catholic. I feel that i can't do anything right with myself or life. i am very promiscuous and i feel very lonely. i admit, i am quite selfish and rude, but there is another side to me. i wouldn't call myself bipolar. but i do care for people and my family very much so. i am doing so well in college right now with a 3.8 ulative gpa for someone who wants to pursue medicine. and i have seen a psychologist already, back way in high school! can anyone please give me an advice? i am really seeking serious advice. thank you =)