Sometimes you don't need to hear their excuses or what they have to say for themselves because their actions already spoke the truth. (They cannot be trusted...ever!!!!)
Ask yourself this when someone says you can't do it. What's holding you back? Exactly. Nothing but them and you, but only because you are letting them.
Dear Self. You know what they say about perfectionism...don't you? Why you don't have to be perfect, and in fact it's necessary that you don't try to be.