Marriage is a legal arrangement. It's primarily about taxation, about rights to make decisions for your partner, and so forth. Love is nice, but it isn't remotely required for marriage.
I'm not dismissing that loving someone is a powerful thing, but if you didn't want to get married because you love them so much, you don't have any room for complaining about alimony, which naturally results from that decision to get married.
If you don't want to deal with splitting shared property and alimony and all that, just . . . don't get married. Simple.
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They contributed plenty, you're just not valuing their contributions, but that's fine, that's why we have courts, so these decisions are made by third parties who aren't emotionally biased and who can work out the just solution.
It's not like alimony is automatic. I'm divorced. No alimony. We both worked while we were married (no kids, yet, in retrospect thankfully), neither of us really made more than the other, so it wasn't worth bothering.