I am speeding down the road of my life toward year 27, and I have found but one place faith and hope dare not tread because they can not...and that's in a relationship, friendship or romantic, and sometimes even family, where trust has been irretrievably lost.
While I do believe that God in His omnipotence can fix anything He pleases, human beings are not like God, because we have been gifted/cursed with this thing called memory. Like Elton John said in "Sad Songs (Say So Much)", "Ironing out the rough spots, is the hardest part when memories remain." Unlike God, who washes away your sins and never remembers them again, people can and do remember. Forgiveness, faith, and moving onward, upward, and forward is possible in any hurtful situation I can think of except where someone no longer enjoys your trust or the sense that they are credible. If you have reached the point with someone where you no longer believe what they say or have serious doubts when they say it, then the best thing you can do is just move on, because that can never be fixed. As the saying goes, once that happens, it truly is all over but the wailing and the gnashing of teeth.