OP [use a comma after the name of a person you are addressing],
I'm not sure if you really want the rules, which I think you are really just trying to excuse yourself from [set off parenthetical asides with commas], but the rules really aren't all that hard. But if you are writing on a forum like this one [use a comma after a conditional phrase)], I don't think your comma usage matters all that much. Proper usage is helpful when you are, making a formal argument, writing a formal paper, writing to your Aunt May, writing a business letter, or writing to snarky people like me [use a comma between items in a series]. Educated, intellectual, uppity, grammarians [separate lists of adjectives which have a unified meaning with commas] do care about commas, little basement-dwelling posters [but don't separate unrelated adjectives] might not.
I'm not sure if you really want the rules, which I think you are really just trying to excuse yourself from [set off parenthetical asides with commas], but the rules really aren't all that hard. But if you are writing on a forum like this one [use a comma after a conditional phrase)], I don't think your comma usage matters all that much. Proper usage is helpful when you are, making a formal argument, writing a formal paper, writing to your Aunt May, writing a business letter, or writing to snarky people like me [use a comma between items in a series]. Educated, intellectual, uppity, grammarians [separate lists of adjectives which have a unified meaning with commas] do care about commas, little basement-dwelling posters [but don't separate unrelated adjectives] might not.
If there is a god, I want to believe that there is a god. If there is not a god, I want to believe that there is no god.