Does everyone deserve a second chance?

Absolutely not. Some people have absolutely no intention of using that chance to make amends or to rectify the situation they created in the slightest. Their only aim is often to get back into your good graces so the situation or you can remain beneficial to themselves for little more than basic human selfishness.

For most it is easy enough to apologize, but they forget they don't get to decide if and when the other person accepts it, how long they take to get over the hurt and betrayal and what the fallout and grief of that looks and feels like to them. They can choose not to stick around and put in the work to regain the friendship, love or trust of that person if they give enough of a damn, but more often than not.. most feel like the other should just "let it go" quickly when odds are whatever they did was trailed over days.. weeks and perhaps months to years. Expecting someone to be over heartbreak or betrayal so we don't have to feel bad about ourselves is utter bullshit. They get over it when they get over it. Even if that time is never. The flip side is, once the other has forgiven it, they don't get to keep bashing them over the head with it for leverage. You either forgive it or you don't.

on either side, if it feels bad/wrong, it probably IS. Just move on to people you can trust.