You are the problem of your feelings, if you only find sex as interest of your relation you have some serious issues.

If you don't feel like sharing your life, then stop the bs now before someone gets really hurt.

Mariage is not about sex, relationships to. Sex is a nice thing that people in a relation or mariage do (without relation to but thats not relevant for now).

Thats what is wrong with most people, you have been duped in thinking love is sex and thats it. Thats why only a little percentage of the populace really is happily married.