Realise that it could happen. My wife might cheat on me as well, it could happen.

As long as you always keep improving yourself, the chances of it happening become lower and lower, but never 0. That's just a fact of life.

I love my business, but all it takes is a few bad months for it to go bankrupt.

My new watch is pretty damn nice, but all it takes is slipping on ice and smashing it on the ground for it to break.

My iMac is pretty awesome, but all it takes is moving it a bit, miscalculating where the table ends, and it ends up on the floor.

My wife is wonderful, but all it takes is me being beta enough for a long enough period, and a Chad to come along + some alcohol, for her to cheat.

So, enjoy what you have with the girl. Odds are she won't cheat, but if she does - you've improved yourself enough to the point where you won't have an issue finding another one.

Don't get overly attached to the things in your life.

The only thing you should have a "oneitis" for is yourself. Not any other woman. Not objects. Nothing but yourself.