The obsessive part of love only lasts for three or six months, so it's not important in the long term. Think about it as an extra motivation to pay the initial costs of establishing the relationship. It would be evolutionarily maladaptive to become forever obsessed with your significant other, unable to focus on tasks of daily survival.

This is the part of love that most people get wrong: basicly anyone who gets their important life lessons from Hollywood movies. Hollywood describes the obsessive part as the "true love". People following this definition get into the predictable cycle of forming a new relationship, enjoying it intensely for a few months, noticing their obsession disappearing, interpreting it as an evidence that this actually wasn't the "true love", breaking apart and starting a new relationship... which again follows the same schedule; and some people can do this for decades. -- If this is what you noticed and want to avoid, you have a good point, but you are taking it too far.

(Some people express it cynically by saying that the main difference between eternal love and casual fling is that the casual fling lasts longer.)

I don't think about love as a blind precommitment forever, but rather like this: I found a person who cooperates with me in a Prisonners' Dilemma, so the game theory is telling me to keep cooperating... if the other person keeps playing by the rules, possibly forever, because that's the winning strategy. Of course there is some imperfection in humans, and some noise in human communication, so I'm ready to forgive some minor problems. But that's still because I am profitting in the long term. -- If I would realize that my significant other abuses me, I would get out of the relationship. The important part of love is finding a person who is able and willing to reciprocate love. (Many beautiful people aren't.) Also, being that kind of person. (It's a learnt ability.)

As a data point, living with my girlfriend makes almost every day of my life better. Just eating breakfast with someone else is better than eating alone: if I multiply it with the expected remaining days of my life, that's a huge stack of utilons; I would be stupid to give it up. And that's just the fucking breakfast. On a boring ordinary day. Which happens automatically, without me having to do anything special; even on days when I am tired or busy. -- For me the conclusion is obvious. But it took years of learning and experimenting.