That's a alot of cars to just maintain let alone complete. Bigtime. I know you hate to do it but sell a few and concentrate on one or two. Ok even then if you did sell a few off you could still spend all your free time on just one car. I admit you are on crack
My advise, if you want it, straight up no sugar coated bs. You are only 23. You have plenty of time to get married. If she can't handle it now.. just imagine married life when she owns you. She should be glad you are not out with your friends, at the bar, hitting on chicks and cheating on her worried. Instead your at home doing what you love, busting your but working 60 hrs a week, making money, learning and developing your mind. Not good enough huh?!.. ..You might have to let her go. Is she really the one? Or just a hottie?, to hard to let go....I have been where you are. I'm 39 much older, my most recent said "for now it's good you have your cars but when we get married we are selling them." 6 months later I was single of my choice. She was also lawyer doing family law so that was a factor too lol. I don't care if I ever get married either, riddles... There are plenty of fish in the sea. You have your Z car hobbie, You are her hobbie.... A recipie for disaster...
I don't know you personally, so how can I give you advise..
But will tell you this. Unless you have to means to throw away cars for your enjoyment...and most of us don't (i don't either by the way. ) She sounds like is going to make you choose, which is lame in my opinion.....So prepare yourself for that. Good luck.
For referernce I will be single forever