Elder John H Groberg gave a talk on The Power of God's Love in General Conference October 2004. It had such an impact on me that I have never forgotten it and every time I feel a need to understand "true love", I refer to this talk. This is an excerpt from that talk.
What is it about true love that touches every heart? Why does the simple phrase “I love you” evoke such universal joy?
Men give various reasons, but the real reason is that every person who comes to earth is a spirit son or daughter of God. Since all love emanates from God, we are born with the capacity and the desire to love and to be loved. One of the strongest connections we have with our premortal life is how much our Father and Jesus loved us and how much we loved Them. Even though a veil was drawn over our memory, whenever we sense true love, it awakens a longing that cannot be denied.
Responding to true love is part of our very being. We innately desire to reconnect here with the love we felt there. Only as we feel God’s love and fill our hearts with His love can we be truly happy.
God’s love fills the immensity of space; therefore, there is no shortage of love in the universe, only in our willingness to do what is needed to feel it.