You don't need to respect someone to love them. Not in the least.
Love is an emotion. It's like saying "What is pain?" or "What is hunger?". Since it's a basic experience, through which you describe other experiences, you might as well ask "What is an experience?". You can define it, but you can't say what it's like, because the whole point is that either it's itself or other things are like it.
People get way over the top about love. You don't have to want to spend your whole life with someone to love them. You don't have to 'have your heart broken' to love someone. When you feel love, contrary to popular belief, you won't instantly know. You don't have to do anything - you either do, or don't love someone. It's like joy, but more. No one can tell you when you're happy, but then it's not always easy to know when you are happy anyway.
That's most romantic love, anyway. It's just a deficiency in the English language that we use the same word for lots of things.