So let me understand the highlights of this relationship:
1) You've been engaged for six years but haven't had a wedding.
2) Your sex life isn't satisfying you.
3) He's cheated on you not once, not twice, but seven times.
Why, precisely, are you still with this poor facsimile of a man? What do you have to gain by being stuck in a relationship that isn't going anywhere and isn't making you happy?
Unless you are currently in prison for murder or oozing puss from multiple open wounds, I am certain you can get a better guy than the one you have now. Please cut this... thing... lose and find someone new, healthy, sexually alert, and able to make you happy.
Ladies, am I right or should she try to make this work?