Regarding the incompatibility... I think it is very important to a relationship, but is not the entire identify of a relationship. Think hard about what you really need and don't back down on those needs. But if you are truly falling in love and you are only mildly compatible, I would say give it a try. If you both truly love each other, the sacrifice of what is left out will be less painful, and you both may be willing to try things outside of your own needs to meet the other's needs. But make sure your needs are met! <3

It also depends on what makes you "incompatible". My fiance suffered through our first 6 years together with hardly any sexual interaction (psychological/physical inhibitions). He had a healthy drive and mostly relieved himself through porn. This year, I have overcome my physical limits and am working on my psychological limits. Our sex life is now the best he's ever had in his many years on this planet. Now that I know how great sex is, I am amazed he stuck it out with me this long.