DH and I were having a chat about an hour ago while I was folding blankets on the sofa before we went up to bed. DH came up behind me and smacked me on what I'm assuming he meant to be the bum, but he missed and got me in a bit of an odd spot above and to the side. He hit me hard. It really hurt, and it made a massive cracking sound. I didn't see him do it and I was shocked and I saw red. I spun around and smacked him back in the face. DH then started shouting at me, told me never to hit him again, that if I did he would punch me in the face. I was also saying to him not to hit me again, that he had really hurt me. He mimed punching me in the face, I'm not sure if he was trying to scare me or he was going to really do it and caught himself.
DH does this all the time, he'll smack me on the bum and say he was just messing around. But it hurts me. We're pretty even height and weight wise (I weigh about a stone more than him, and we're both 5ft10") but he's ridiculously strong. I've tried telling him to stop doing it, explaining that he doesn't know his own strength and it actually hurts me. Sometimes it leaves red prints behind he does it so hard. Also today, when he hit me it kind of made me jump/try to move out of the way and I twisted my knee as I was stood on the rug, and that's killing me now (I've been having some prior issues with it).
I feel absolutely awful now though, I hate that I hit him back like that. I was just so, so angry and I flipped out. I hate that I hit him. I really want to go upstairs and apologise and beg him to forgive me, but then part of me also thinks that he should be the one to apologise to me, because he hit me first. But I doubt he'd ever do that. I did go upstairs and ask if he wanted to talk about it about 20 minutes ago, but he said no.
I wouldn't mind the occasional flirty bum smacking type of thing but I think what upsets me the most is I've told him he hurts me, and he just seemed to put all his force into it.
I don't want to break up with him, we've been together for 15 years and I love him and he's a good husband. He has been really tired and stressed with work lately and he was in a bad mood today, so I think that he just won't have meant to do it as hard as he did?
I'm devastated and don't know what to do.