I also have endometriosis. I've been battling it for 17 years. You can most definitely continue to have endometriosis following a hysterectomy. In actuality your endometriosis didn't likely "come back" but rather was not completely removed.
It can be enormously difficult to find a doctor with the knowledge and expertise to recognize and remove all endometriosis. There are a few endometriosis specialists located in different areas of the country who are the ones most successful in treating endo properly. It was one of these specialists I sought out when I finally gave up on my local ob/gyn. I traveled across country for surgery with the endo specialist...it was the best thing that's happened to me since I was diagnosed in 1987.
If I can answer further questions or just share more of my experience I'd be more than happy to do that.
-- Debbie