I have such a problem: I'm afraid to get checked out because they will…

I have such a problem: I'm afraid to get checked out because they will be taking blood constantly ? I have apathy ? everything because I keep fainting when they take blood, it doesn't matter if it's from the vein or finger! ALWAYS! Valerian also doesn't help, I always tell the doctor give me cotton with valerian and all the same I lose consciousness ? how can I do? After fainting like that... that's really bad.... and go for tests and know that I'll be so badly afterwards as on a forced march .... maybe there are others like me? How not to faint during blood draw?