Ahh, that gives me a slightly better idea of what you mean by using the term self esteem.
For sure the examples of marriage around someone makes a pretty big difference - both my fiancee and I have parents who have been married decades, but in some ways, we've noticed ways in which they aren't compatible and there were long stretches where I'd say neither marriage was entirely awesome, but maybe that just happens at certain points.
But I think an even bigger overall factor (but made up of many different concepts) is how our society views marriage, relationships, and individual identity. Most people have very little core identity or confidence to begin with and view marriage as a bunch of things that seem completely made up or outmoded to me. For instance, the idea that someone else "completes you" only works in a very specific sense - ultimately most people I talk to seem to in one way or another think it's okay to have someone else complete your core identity.
I almost wrote an ebook on this at one point, but I strongly believe the two people in a relationship first and foremost need to be independent people with their own identities. And then incorporate eachother as much as they way. Most people I know seem to just meld into their partner and their relationship becomes on big blob of dual-identity. Visually I like to think relationships should be two circles (people) joined together, but not completely overlapping. It should be more like a Venn diagram where you can still tell there are two distinct circles, rather than a big amorphous blob circley thing.
Hopefully it's either clear or now can be clear I'm not really bringing this up in a personal way, more just b/c the subject is kind of brought up in general and now I'm hijacking your thread,
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