Ender works hard to express his feelings in private and not show homesickness in front of any other person.
Questions have to do with this sentence.
Expressing his feelings in private is much better than not expressing his feelings at all. Ender is really just a child being manipulated in a very adult environment. There really is no way out for Ender so expressing his feelings when he thinks he is in private probably enabled him to keep his sanity. Not showing feelings may help Ender keep control in matters of conflict and war but those feelings eventually must be dealt with, a person's psyche has to have an outlet. Ender wasn't given any guidance to deal with many of his emotional struggles. The people watching him wanted Ender to steer through them himself.
