Very heavy discharge except during sex?

since i was younger, and first starting puberty, i have always had this heavy discharge. all day, every day, allll thhhee timmeee! i used to wear pantyliners it was so bad, but then i stopped and it lightened up a little but its still there. i used to cry about it and its very uncomfortable because i have to wipe like every 30 minutes, and its not always easy to make a trip to the bathroom to do that. its also worse after i pee. i will go to the bathroom, wipe, and leave the bathroom but about 5 minutes later have to go wipe again. now the only time this isn't the case is when my fiance and i try to have sex. i dry up like a friggin desert! lol the only way i can get wet enough for sex is for him to make me "***". now after all that graphic detail...is this normal? should i have discharge, so much, all the time? and why do i dry up right before sex? any advice would help! thanks! :)