If you ask me, I'll say all the three leads to same outcome really, however I'll answer this questions very practically and to the best of my understanding, there are different kind of love but from your question above I'm guessing you're talking about sexual love or love towards the opposite sex and not natural or agape love

Love for me is displaying deep emotion or endearing affection towards a person of the same or opposite sex. Now love involves sacrifices, a feeling of wanting to be near someone, sharing special moments and having sharing sexual entabglement with them.

Obsession on the other hand means not being able to control the way one feels, thinks and want someone or something. Obsession happen when you love someone but it seems they're not interested in you and in a bid to get that love at all cost they end up being obsessed, wanting to b4 possessive at in some cases very jealous and displaying displaying dangerous behaviours.

infatuation is quite different this one works with with the phrase "love at first sight" it's means showing an ephemeral feeling and desire towards someone, however it's often related to lust because the feeling isn't deep and doesn't last long. These three sometimes happen in sequence in strange situation, but the most dangerous of them all is obsession.