Giving/ receiving oral

Reggie
Ok so when it comes to giving my wife oral, I can make her cum real hard or every time I give it to her. She likes giving me head, but it takes her a while to have me cum, most of the time, I don't. Crazy part is, when I feel like I'm going to cum soon, she either stops or sucks it differently and it won't feel as good. She says she has to take breaks because her jaw begins to hurt, so most of the time, I just start jacking off and she will swallow then. I only had one person in my life make me cum every time I got oral, even when I was drunk, and tell her how to suck it good, but she just can't do it right. How can I have my wife give me head to were it's not hard on her jaw, and cumming in her mouth without my assistance? Sorry for the long post, but need help on this issue because she loves when I do cum in her mouth, but hates that she can't make me cum. Any ideas ladies?