I feel for you because I was right where you are a few months ago. Exactly the same situation actually...I'm sure there are other options we missed but the choices we faced were these:
1. Travel back and forth on vistor's visas (expensive and limited)
2. Enroll in classes to get student visa (limited to when school's in session)
3. Sponsorship to work (hard unless you have a talent the UK wants ie, doctor, teacher, etc)
4. Fiancee visa (just as much as the marriage one)
5. Marriage visa

It's different of course because your relationship is different, but we realized that even though we were getting married far quicker than we would've without this visa hassle, we still wanted to get married. The idea of being without each other was far scarier than moving forward with it. So we headed to Vegas and got married (minus the Elvis). Now he's back in the UK getting things set up so we can apply and move me over. I don't know if this helps any, but try to remember that not everyone has to overcome such hurdles to be together. By fighting to be together you're actively showing how much you care about one another, something that is quite rare in 'normal' relationships.