What is love? And the difference between it and infatuation?

What is love exactly? And i mean romantically, I have a daughter and there is no other love like what i feel for my baby, what i want to know is how do you know or feel when you are really in love with your significant other? Ive had my fair share of boyfriends and observed other couples and marriages, but it never seems to last and i don't think ive ever been in love, i've been infatuated and lustful but not love.