You bear it by working hard to get ready. You bear it by having good people by your side. You bear it by not just hoping but knowing you can handle a lot, because you already have. At least, that's what always worked for me.
You can't keep snakes in your backyard and expect them only to bite your neighbors. You know, eventually those snakes are going to turn on whoever has them in the backyard.
You've got to be willing to stay committed to someone over the long run, and sometimes it doesn't work out. But often if you become real honest with yourself and honest with each other, and put aside whatever personal hurt and disappointment you have to really understand yourself and your spouse, it can be the most wonderful experience you've ever had.