What do I do about yellow vaginal discharge? I've had a hysterectomy and I'm not sexually active. It gets worse when I have a bowel movement.

Unsure. Your could have a fistula from your bowel to your vagina - you need to see your doctor for a definite diagnosis ant treatment.
Fistula. You may have a fistula ( connection between bladder or rectum and vagina ) have a good examination by your gynecologist & may need to consider further testing, including infections.