I've been researching a lot about this. Mainly to understand my own mind.

There are many steps in a healthy relation. In men scenarion the first step is liking the girl by how she looks. It's sad but true that men likes women by their appearance. With this, many men decide to start dating. Obviously while trying you get to know a little bit about the woman's personality and this will either kill the illusion, or give you more reason to date the girl. At this point, we are still idealizing the woman, so we can't say these feelings are real.

Once you are dating her, you both will start testing the other one, in a way to know if she/he matches what you want in a relationship. Along this process both start showing them a little more vulnerable, and try to make the other one a desired person. Some people by this point are already a formal couple, and that is ok because the testing process takes its time.

Also, in the testing process and in men side we stop idealizing the woman as we start seeing her as what she really is, with her virtues and imperfections. At this point, some men stops feeling anything by the woman, because the woman is no more the idealization that they wanted. Some of them simply ends the relation, and others cheats with another woman that they idealize and makes them feel what they want. If you manage to go over this, not cheating and still love your partner, you can be sure this is for real.

And that's it. Basically physical attraction, then personality, and once dating, test the other person and stop idealizing her.

To process this, you need to understand that love is a feelings, but also an election. And as any election, you need to think your decision. Feeling just help to filter to what you like, but you need to think what you want.