Building emotional ties between the readers and characters

Building emotional ties between the readers and characters will always cause the reader to remember the character. Let’s say, what if the character lost an arm while holding onto a stranger as she was falling from a train? After months and months of pain bitterness took over his life. He is continually asking himself, “Why did I try to help? If I didn’t help she would have died.” The character is in physical pain as well as mental pain. This has left the readers with all kinds of emotional thoughts: He really shouldn’t be so down on himself, after all he helped the lady. That lady should thank him every day of her life for saving her. In my mind he’s a hero. If I was in that situation, I would have done the same thing, but he lost an arm doing it. I feel so sorry for him. Oh my, the pain it caused. He could not do, with one arm, what he could do before. How is he going to manage his life? Why did this happen to such a good person?
So many thoughts are going through the readers mind when the character is suffering. This build such strong emotions that the reader will want to continue reading, to see if the character came to peace with his situation. Will he be strong and make it to the end or is his life over? The reader cares so much about the character, that they carried him through riding on their emotions.