How many times are you capable of falling in love?

I heard people say they can only fall in love once in their whole lifetime and that’s it. Are they just being overly romantic or too scared to admit they can’t deal with heartaches that well? I could understand the fear of losing someone and ending up starting over again which would be to say the least, a real drag. But then there are those who do not seem to mind falling in and out of love in a click of a finger.