What is the difference between love and infatuation? What is the difference between the two or are they the same?
I reckon if you marry someone because you want to keep them, that's like infatuation.

And if they're dying, and you neither want them to remain in suffering, nor want to push them away, that's more like love.

More generally any form of unwise or selfish misbehaviour might be diagnosed as caused by an "infatuation", whereas ethical and generous might be described in more positive terms like "love". Buddhism might distinguish different types/kinds (manifestations) of the better kind of love -- see the "brahmaviharas" which are translated e.g. "compassion" and "loving-kindness" and so on.

There's another consideration, I think "ethical" might imply that nobody regrets it, it's not action (or intention) from which any suffering or dissatisfaction arises -- so it "benefits both, self, and others", and see e.g. "and is a small taste of Nibbana".

If you want specific advice about binding yourself to (or simply choosing) a lay partner, see e.g. Any authentic sutta from any tradition that gives guidance on what kind of partner to choose? -- see also e.g. DN 31 for very generic advice about friendships in lay life.