Confusion in Great Expectations

In Chapter 6 there are some confusing parts and this passage was confusing to me:

"The fear of losing Joe's confidence, and of thenceforth sitting in the chimmeny-corner at night staring drearily at my for ever lost companion and friend, tied up my tongue. I morbidly represented to myself that if Joe knew it, I never afterwards could see him at the fireside feeling his fair whisker without thinking that he was meditation on it. That, if Joe knew it, I never afterwards could see him glance, however casually, at yesterday's meat or pudding when it came on to-day's table without thinking that he was debating whether I had been in on the pantry. That, if Joe knew it, and at any subsequent period of our joint domestic life remarked that his beer was flat or think, the conviction that he suspected tar in it would bring a rush of blood to my face. In a word, I was too cowardly to do what I knew to be right, as I had been too cowardly to avoid doing what I knew to be wrong." (Ch. 6, pg. 40)

From this I understand that it is about how Pip is too cowardly to admit to doing something he knew wasn't the right thing. What I don't understand is what is hidden in this passage. I think there must be something important in the passage because it could have been said a lot easier and shorter. Thanks for your help!

Group essay

1. In my paragraph I am changing a few things. I am going to be changing my first concrete detail. It will instead become the second quote moving my original second one to the first. This quote will be more of a paraphrasing of the part when Cecily is confirming that Algernon is Ernest and Jack isn't, but is also the part where she finds out Algernon is really Algernon. My commentary for that quote will be accordingly different. It will be about how they have fallen for the person in their head, but they are becoming confused with the real one who isn't like they imagined. I am going to change around some of my other commentary a little bit, but not huge significance.
2. The main thing I am having trouble with is the concluding sentance. I don't want to repeat myself and just go over everything that I have just said, but I don't want to say something new and confuse a reader. From what you guys remember of my paragraph what should I do?