If we forgive others does this mean God forgives us when we sin in a way we can’t rectify or often don’t rectify the issue?
The ArtScroll version of the Gemara in Yoma 23a says (see here):
But didn’t Rava say: With regard to whoever forgoes his reckonings with others for injustices done to him, the heavenly court in turn forgoes punishment for all his sins?
The ArtScroll version has a footnote, which quotes Rashi in saying that if a person who has been wronged by another, forgives that person, and thus he relinquished his right to exact retribution for the wrongs done to him, G-ds attribute of Justice will relinquishes its right to exaxt punishments for the sin(s) that person did.
In a similair vein, in Tomer Devorah, it is explained that:
When a person who was offended accepts an apology from the wrongdoer, overlooks an offense and agrees to restore a friendship to its previous state, even though the damage was not corrected, Hashem in turn accepts the teshuvah of the Jewish people. He forgives our sins entirely, and His love for us grows to a level even higher than it was before we sinned (The Elucidated Tomer Devorah, p. 106 by Rabbi Shmuel Meir Riachi)