Words of advice: Why is writing so confusing?

There are so many rules on words that sometimes I think people are just trying to screw with my head. Here are some examples I've learnt in the last few months.

RULES:

1. Toward = American Vs Towards = English.
2. Fiancé = Male Vs Fiancée = Female.
3. Blond = Male Vs Blonde = Female.
4. That = Introduces an essential clause (no comma) Vs Which = Introduces a non-essential clause (comma).
5. Farther = Physical distance Vs Further = To pursue a topic; addition.
6. Lay = To place Vs Lie = To recline; tell a lie.
7. Discrete = Separate Vs Discreet = Secretive.
8. Loath = Reluctant Vs Loathe = Detest.
9. There was also one about Dialogue Tags Vs Action Tags that had to do with Comma Vs Period/full stop.  I just know it's fricken important... I always manage to get it wrong. 

Here is what my amazing editor Jamie D R sent me to help me keep track:

Dialogue tags are when the speaker is saying something and the tag clarifies who. For example… "Johnny, come away from the window," his mother said. Other words used in an action tag might be cried out, replied, screamed, whispered, etc. Dialogue tags are separated from the dialogue with a comma and the tag is not capitalized.

Action tags are those that more delineate the action of the speaker. For instance… "Johnny, come away from the window." Johnny's mother sighed. Other words commonly used and confused with dialogue tags are laughed, snorted, hiccuped, etc. An action tag is separated from the quote by the fact that the quote ends with a period and the action tag is capitalized and its own sentence.