Tubal Ligation and Endometrial Ablationa at the same time or a hysterectomy

I recently had an ultrasound and was diagnosed with having adenomyosis (lining moving into uterus wall). My doctor recommends tubal ligation and the ablation at the same time. He also informed me if that was not successful then I may have to get a hysterectomy. I'm trying to decide if I should just skip the tubal ligation and ablation and just get a hysterectomy. I've been reading up on both and there seems to be alot of negative things about both. I'm concerned with side effects such as weight gain. I'm also worried that the ablation may not be successful if the lining is too far in the uterus wall I may end up with heavy periods again. I've read that some bleed for months after the ablation and they regret getting it done. I'm 30 and always suffered from heavy periods and pain during intercourse (which led to my diagnosis). I have 2 children and my husband and I are not planning to have anymore. After my 2nd child, my periods got heavier. I do not want to be on birth control in fear of gaining weight and I'm not good with pill taking. I need advice on which one is better with the least side effects. If anyone has been through this or is going through it, please feel free to share your experience as well.