Love is a commitment.

Although feelings will accompany love, and although sex will be a part of marriage, a lasting, you cannot base a healthy relationship on these things. In the long and winding journey of life, infatuation, sex and other such details will slowly vaporize and all that would be left in the relationship is commitment and understanding between the partners.
There are several other factors which could go into the definition of 'real love' but then again they would vary from person to person!