One of the most comprehensive Mitzvot of the Torah is the Mitzvah of "Ahavat Israel" - love for one's fellow Jew - which our Talmudic sages declare as a "great principle of the Torah" and "the foundation of the Torah.".
Essentially, the mitzvah points to the unity of all Jews, as if they constituted a single entity. As such, any action by any Jew, whether positive or negative, has a consequence for the entire Jewish people. Indeed, the observance of mitzvot by any individual Jew provides the Jewish people with impressive strength.
Every Jew, wherever he or she may be, even a solitary Jew at the farthest end of the earth, must remember that he or she is part of the Jewish People and a representative of the entire Jewish People - the same people from the time the Torah was given at Mount Sinai until the end of time.
The division of Judaism into "Orthodox," "Conservative," and "Reform," etc., is artificial. All Jews share the same and only Torah, given by the same and only God, although some Jews are more observant than others. Labeling a person does not change the essence of being Jewish.
The three loves—love of God, love of Torah, and love of neighbor—are one. They cannot be differentiated, for they share the same essence. And since this is so, each one encompasses all three.
Therefore, if one sees a person who has love for God but lacks love for Torah and love for their neighbor, one should tell them that their love for God is incomplete. And if one sees a person who only has love for their neighbor, one should strive to draw them closer to love for Torah and love for God, so that their love for their neighbor is not only expressed in providing bread for the hungry and water for the thirsty, but also in drawing them closer to Torah and God.