Speaking for myself, ending the 2 relationships that had a strong BDSM component were the most difficult. More existed than BDSM, so it was like ending both a vanilla relationship and a D/s one at the same time. It definitely took a long time to recover emotionally. Plus, I've ended every vanilla relationship I've ever had, and in all of them, it's been about 70% due to me recognizing that my partner is truly, honestly, 100% non-dominant. It's not something I can live without for long; I'll never be satisfied in a vanilla relationship, including one that has a few sprinklings of S/M, so that makes it easier when I do end them.

I don't object to Thir's comment quite as much as others have because in a couple of specific areas, it's been true for me. I still went to work, bought groceries, vacuumed the house, etc, but internally I was certainly a mess. My first top-ish partner helped me work on a lot of stuff, including my major guilt complex. He would punish me - usually physically, usually quite painfully, and always difficult for me - when I messed up in my life. When I ended that relationship, I had to figure out other ways to deal with myself, and that certainly took some time to do.