postpartum bleeding that has lasted 9 months?

Okay, I gave birth to my 5th child in February of this year. She was a c-section baby, so they made sure to get all of the placenta out and then cleaned out my uterus pretty well with a sponge. I bled for 14 days, then stopped bleeding altogether. 2 weeks later, I started again, and it's been going ever since. Sometimes it's like a full period (heavy bleeding, I might leak through a tampon AND pad overnight some nights), other times it's just spotting or very light bleeding. Now, I've been in contact with my doctor about this... 3 months post partum, she put me on the pill, which did NOTHING. Then, after a month, she put me on the shot, which didn't help (I've been on the shot before and didn't bleed at all)... then she put me on the cascading birth control with the shot, where I took 4 pills a day for 4 days, then three, then 2, then one, until I was out of pills... that stopped the bleeding while I was on the pills, but the day after I stopped them, I started bleeding again. I contacted my doctor again, and she wants to do a biopsy. I've had 2 ultrasounds, which show nothing. I had my tubes tied during my c-section, but she said that shouldn't cause this. I have also been getting cysts on my ovaries, which have me in bed for days, crying with a heating pad on my gut. During the c-section, they did visually confirm that I have endometriosis, which was suspected for years... now I'm at a loss on what to do, or what this could be. I have to wear either a tampon or a pad constantly. Occasionally I will have one day with no bleeding, and then it goes right back to it. I'm tired all the time, I bruise easily, and I'm worried this is affecting my iron levels, but my doctor doesn't want to perform a partial or full hysterectomy. That's my OB, but I also have a new primary care doctor, and I am wondering if it would be more beneficial to me to bring it up to him, or to continue seeing my OB about the bleeding. Anyone else gone through this? What happened with it? And which doctor should I talk to? I'd like to have a hysterectomy, since I do have the endo and the cysts, and I am done having children. I'm 29, and this is my 5th child, so those shouldn't be a factor. My OB is through a Catholic hospital, and it took a lot to get her to tie my tubes. I'm tired of hurting all the time. This is affecting my life, and I don't know what to do. Ideas?