My grandma beats my ass

I just turned 20 and my grandma beats my ass. Sometimes it's with a cane, sometimes it's with her hand, and sometimes it's with what she's dubbed 'the spankin spoon.' It's an old wooden spoon that she uses to make spaghetti sauce. She doesn't use that one quite so often anymore because a while back on a particularly brutal beating she broke it on my ass. Obviously since I'm older the spankings don't really hurt. Not that much anyway. When I asked why she still even bothers she responded that it's more so I can feel the humiliation of getting my ass whipped by my own feeble little grandma. But I don't care. I'm a total asshole to her. I'm mean spirited, ungreatful, entitled, and I fuck off my school work all the time and she pays for my schooling so she has to eat it when I fail a class. I've taken to taunting her when she beats my ass lately. I say things like 'yeah give it to me you old bag,' and stuff like 'you hit like a fucking old lady.' It's to the point where I almost love the beatings because it gives me another chance to taunt her some more and try and break her spirit. To all those out there who get beaten by their family members, is it normal that I'm not bothered by the beatings and in fact kind of enjoy them?