A game review would be greatly appreciated! Bear with me - I'm not too good :-(

I (black) played a fairly strange game against MFoG12 (white, 18k). The game was going on when white suddenly resigned with a "I resign. I can't win the game" message. This was really strange b/c I thought white was winning with a potentially large framework in the bottom right.

Here's our game - why did White suddenly resign? I (black) wasn't sure how to prevent white from getting most of the space in the bottom right. I would have probably played something along G or H eventually, although i wouldn't have been able to prevent white from keeping most of that space.



So after this, I saved the SGF, loaded up Fuego as white and played on. Since Fuego was stronger (IDK how to lower the Fuego difficulty), it kept playing and eventually won.

SGF is below, and I had a few questions:
1. So how did I do? Anything I could have done better?
2. Turns out the game was much closer than I thought (I thought white would crush black) - I totally didnt read into the close game. How can I improve at this? I feel I'm terrible at reading the score until the game is over. Any tips would be greatly appreciated.
3. Go to move 230 and check out the play(s) - comments below
a) the main variation is me playing. I didnt think there was anything else I could have done so I was starting my endgame passing. Why was white keeping on playing? What could I have possibly done in the big open white territory? Looking back (comment in move 235), the game seems to have been much closer than I thought (W+1.5), ATVL as per Fuego's scoring. How can I improve at reading score mid game?
b) The variation at 230 is Fuego playing both black and white (b/c I was curious what could black possibly do). Black mounted an attack but white eventually won. So what was the point of even playing on? Hoping the opponent makes a mistake?
c) The variation at 233 was me playing as white and Fuego as black (we switched sides) b/c I was wondering if I had a better play as white. It didnt really matter b/c white won again. How does my play compare with white's plays in the above variation (see "b")?

That was a long and meandering post, but hopefully you folks will have some answers and feedback for me :-)

Look at your move -- can you see whether M12 is a real eye? Can you find a better local move for ?

N10 would have probably been a better move... It was something I had thought about but it didn't seem like a huge deal since I had planned to connect along the right. That never happened since I got sidetracked and white eventually took those with 86.

EDIT: Crap, I just realized I could have saved them by taking at Q10. AAAARRRRGHH. I totally missed that until now >:-(

I played what I played since that was the only thing I could think of...