The strongest possible message of love is the Thumos Love message. It is literally the text string FB.com/ThumosLove. It has exactly 17 characters, which can all be in lowercase. To send the strongest possible message of love to your friends, send these 17 characters: fb.com/thumoslove.
This is the strongest possible message of love from you because it is the link taking your target of love to the Facebook page that spells out how you plan to actually carry out the act of loving in specific steps. These steps are backed by the philosophy as explained in depth by the 2017 book THUMOS: Adulthood, Love & Collaboration.