Sometimes I am too chicken to give up my queen

So, how can you prepare to play games like this without the queen? As a side question, what should you be thinking on move 13? I thought I should develop the knight. Why didn't it work this time?

Well there you were forced to give up the queen. However, the resulting material imbalance should be good for you...ok you are down a pawn but 2 bishops + a knight should be better than a queen. As a general rule when thinking about exchanges it is usually the side with more pieces which stands better eg.3 minors vs Queen, 2 rooks vs Queen, 2 minors vs rook. It depends on the specific position of course, but usually the stronger piece cannot achieve as much alone as the weaker pieces can achieve working together.

On move 13 I would be concerned about white playing Be3 and my queen running out of squares. I think 11.Bd6 was the move which made things awkward, with this you are no longer able to drop the queen back Qd7. Anyway, as I say you were already up a piece at this point and even though white could win your queen for 2 minors the position was still good for you. 

Thanks, that partly explains what I saw with the engine evaluation. It had Kh1 to get out of the pin and black would play h5 instead. This leads me to believe the answer to my question is to go on a kingside attack. Something like this.

resignation was premature on move 18. 

But to think of it this way: either I give my queen for three pieces or I lose my extra material and an exchange. Although it seems you missed Bxc5 so I don't blame you.

It's not advanced. Either material stays balanced or it doesn't. 

What happened (I think) is black missed the simple Bxc5, believing that he could just give the piece back. If he saw bishop takes c5 also wins the exchange the decision is easier. To quote from @fizzyband's immortal game on his bio, "it is not born of brilliance but because black has nothing else".

No, I meant that the thought process is simple if you see the moves. If you keep your head on you almost anyone with critical thinking skills above the 1000 level can see, "less material bad, equal material not as bad"

Missing the moves is different. That has nothing to do with the thought process.

No, I meant Bxc5. White's move. You have to calculate opponent moves too

beginner and intermediate players can count. It isn't hard. What is hard is keeping all those tallies in your head and seeing that white's Bxc5 moves wins an exchange.