Licking Cum From Her Pussy

My wife knows I want to get fucked but she sort of just ignores it. I’ve told her I also want to watch another man fuck her hard and fill her with cum and then I want to lick it out of her. She has no interest. So I try to lick my own cum out after juicing hard inside her and pretend it’s another man’s load. But she’s onto me and exits the bed before I can get to it. I basically need to be a part time cuck, but my wife is not into it. What should I do?