What’s the difference between love and obsession?

Obsession is selfish. Love is selfless.

true love is wanting someone to be happy, whether that includes you or not in the picture, obsession is purely selfish and can lead to behaviors that will actually make the target person unhappy, something that would be unacceptable to a loving heart.

Restraining Order

Obsession - you don't have a clue what's going on
Love - You know exactly what's going on

Love has no walls, not fences and no borders. Obsession is a prison.

About 5 inches difference

Reciprocation