Do you think we can fall in love again after falling out of love with the same person ?

Actually yes, it's called marriage. We fail to give our relationships a fair chance by being under the false impression that two people can stay "madly in love," for more than a few years at a time. when in reality, that "madly in love" fades, and we are left with real love. True love is understanding and a wanting to take care of each other, even and especially after the "madness" fades.
Experts tell us that in a long term relationship, both people won't be in love with each other at the same time through out the entire relationship, but will be in love at the same time at some point if the relationship is given a fair chance.