Hi AC, So glad to hear from you and glad the article has helped to the degree it has.
First, there is no "out-sinning God's grace" for someone who wants to be forgiven. The only way a person can nullify God's grace is by consciously denying that they *need* God's grace. In other words, they have to decide "I'm going to sin and it doesn't matter," and quit asking for forgiveness and repenting. And by doing so they communicate to God that they don't need Jesus' sacrifice.
But that doesn't sound like you. You express remorse & regret and try to change, and God's grace is there for you.
Second, I'm not sure why you say you have to live a life of isolation, but can you not build a relationship with somebody who you could call a friend without revealing every detail about your life? Even good friends don't know everything about each other, and respect that about each other, while still caring about each other and helping each other out. Since I don't know the specifics, I'm not sure how helpful that is, but no man or woman can go very long without someone to confide in. Even just 1 person they can confide in makes a world of difference.
I'll pray for God's merciful love in your life.