The idea that Hashem loves every Jew is certainly expressed in some seforim. For example, see here in Likutei Moharan:
“God takes pride even in the most insignificant Jew, even in the sinners of Israel, so long as they go by the name Jew. There is a special pride which God takes in each individual Jew. One should therefore never despair of God’s help regardless of any wrong one may have done. God’s love for him will never cease, and he can still return to God.”
And here is something from Matanas Chelko, a commentary on Chovos Halevavos, making clear each person should believe Hashem loves him:
“Certainly, without strong trust in his father, that his father worries for him and loves him, he would never have jumped thereby placing himself in danger of falling to the floor. His trust in his father is so great that he jumps to his hands. Likewise, for a man’s trust in G-d, he must jump into the hands of G-d and trust in Him that He cares for him and loves him just like a father’s love for his child.”