I'm sorry that I can't facilitate you wanking it on the cheap but I just wanted to put in my two cents, if you'll have them.
If you are serious about having a long term relationship with your fiance, then you really need to change the situation. If I were you, I would try and think of a way that the two of you can do this together.
For example, my girlfriend gets way too sore from penetrative sex everyday but she's got quite the sex drive herself. I give her all the oral she wants, and on the days I want to get off she'll suck me dry no question. It's not my ideal situation, but it works and it's healthy. Try working with her to give her multiple orgasms, so that her getting you off manually is more appealing to her.