Love is described as something important in life, something everyone will experience at least once in their lifetime. It’s like an agreement in a way you both trust fully, Care deeply, don’t control each other ad accept you both have your own life.
Obsession is something that is one sided. When you’re obsessive or have obsessive love it feels more possessive. You cant be yourself if you’re receiving this love and you’re limiting the potential the other has if you give it.
Although they seem extremely different and should be easy to tell apart it’s actually quite hard to. Both obsession and love raise serotonin levels and make you feel either complete or empty. The thought processes can be similar too, you fee like you are connected with each other when you are truly distant. Gatsby is a great example of obsessive love or just obsession in general.
Gatsby is said to be in love with Daisy and would do anything to win her back. Many see this as a heroic and huge gesture of love Gatsby is showing. But in reality he’s obsessed with the idea of her. It’s said he found her more attractive to Gatsby when many other guys have loved her before, he fell for the lifestyle she had that he had never experienced, he fell for the house she lived in, etc.
Daisy only wanted superficial things as well. She only wanted a lavish lifestyle and to marry a rich man who has a high status, but also is good-looking. It’s shown when she chooses Tom over Gatsby no matter what he did to try to show his love.
Neither of these is love. Love is never shown in the book itself, it’s always lust and obsession. This is also a way of Fitzgerald saying the American dream had died, love being one of the dreams and it never being mentioned or shown.