Sex before marriage...

I have been a Christian for just over one year now and can honestly say its the best thing that has ever happened to me... i have been in a relationship for 4 months now and as i am quite new to this i am still learning... i know a lot of Christians say NO sex before marriage.. but if you are in a long term relationship and you know you have found the one and will probably marry this person, would you say you should still wait?  part of me wants to do it all properly and wait till the wedding night, she would be awesome and very romantic i feel, however i also feel sex makes you close to someone, how do you get that closeness without having sex?  can anyone help me out... also moving in with fellow Christian partner... should this also wait untill marriage.. but again how do you know you can live with each other if you dont do it untill you are marriage?  and lets face it.. if you get married and then find you cant stand each others 'habits'... what do you do then... DILEMMA!!!