I tend to think of love when it relates to partners in two ways, romantic love and familial love. I think either one can come first or last. For me romantic love is usually foremost, followed by familial love. When the romance ended if I did not have familial love, I don't have a high interest to interact with that person. Familial love which I also have for a few of my friends, feels like a bond that is forever there. When my mind wanders I will think of them and wonder how they are.
I know that I choose to have romantic love. I know when I start feeling love towards a person, and make a conscience decision to let it happen by spending more time with them, or walking away from them.
When in love, I know, because I want to spend time with that person. Their voice, the image of their face, sends me some good happy chemicals to my brain. I do believe that I can steer myself into romantic love with someone where it isn't just by chance.
Then if they become unhealthy for me or unmanagable. Hurt shows up, that are like bricks that go into a wall of protection, sealing off the romantic love feelings. Their voice, their face, no longer has anymore effect than a close family member.
Familial love, I don't know what it is. If it can be switched off, I don't know how to do it.
Also, I can have a sexual relationship with someone without any romantic love. I can develop familial love with that person that never develops into romance. So to me, lust is not love.