Love isn't enough to make a relationship work for a lifetime

And parents and grandparents are often trying to share this with younger people who haven't learned this yet.

To mixed results at best. If this were truly learned you wouldn't have 1/2 of marriages ending in divorce in the U.S.

Equally important to love and sexual attraction is respect, friendship, and economic viability. All these factors are important.

If you study the main reason why relationships end it is because of money not love. There is almost always love in relationships but money and how it is used in that relationship means that relationship is either working or ending or close to ending at any given point.

So, unless in addition to love you have respect, long term friendship, shared interests, want to live in the same place on earth and do, have a good source of income (for now) and hopefully into the future, most relationships won't stand the test of time.

And last but not least both people have to be practical enough to make that relationship work in the short and long term or else it will likely end eventually too.

So, love is both an art and a science to make it through a lifetime of all that happens to people during their lives.