I've been having a problem with over wetness in my anal and vaginal area for a couple years but have no std. i have a sour smell and thick discharge?

Have it checked: You need to have the area checked and proper testing done... - Needs to repeat testing of STD - Other causes might be fungal infection or skin condition like eczema that might be giving you this problem

Lots of things: The differential diagnosis (e.g. possible diagnoses) is vast. I would recommend getting checked out; especially if this has been going on for a while. Good luck!