Hard to do, and I think I can tell by your attitude, that you'll wind up in a way better situation next time. By age 40, I had been through 4 somewhat serious girlfriends, and each relationship was totally different. What I realized this time, with my wife, is that she isn't at all what I thought I was looking for. She found me, and I'd never have even thought of asking her out, as I thought she was way out of my league. I'm not going to explain it in detail in this public forum, but let's just say that how I found my wife "only happens in the movies". Always before I had set my goals low, and I achieved low. What it boils down to, is that I was afraid of failure in all of my past dating habits.
And just to be smug about it, that CK underwear model that my ex-GF cheated on me with 10 years ago, is probably lying on a couch today with a big beer gut, and feeling like a loser after a minute in the sun, and wondering why no women are worshiping his body anymore.
Charles