lol No, it doesn't sound like you wasted your life at all. Sounds like you had a blast. Building your own house is a helluva good idea, as is having a 10 year younger girlfriend. Kudos to you, sir.
Idk if a project can truly ever be finished though. I have friends who have had project vehicles longer than their marraiges or homes. Just saying.
I got thrown out of my home at 15 and had my own place within 4 months. I believe you can achieve anything you put your mind to. Been trying to start over after going broke around 2008 when the economy went bad. I've started another business but have been having a hard time getting it going so I'm truck driving again. (thats my fallback.)
The 93 Ranger, 90 Bronco II, my 72 IH 1/2 ton shortbox (much longer term project) are just hobbies. Getting back to my pre-2008 success level is the goal.