In the ending where Walker chooses to shoot the imaginary Konrad, Konrad has these poignant words to share with Walker, which is put on top of this page. These words are very important as a reminder to both Walker and the player that despite making mistakes there is still hope for the future and we should cling to life so that we have a chance to earn our happy endings. To give up on life would be an insult not only to those we love but would make the hardships of everyone that suffered on our journey a waste, we shouldn't be too hard on ourselves as we still have the right to life and the chance to do better next time.
The way Walker sadly, but surely, says, "Stronger than you were." is very powerful in the context of having just discovered that Konrad had committed suicide. Walker has chosen life, in that sense he really was stronger than Konrad who ended his life rather than living with the consequences of his actions, it takes a strong man to affirm life even in the midst of adversity.
This takes on even deeper significance when you learn, through Walker's flashback, in the Suicide by Cop ending that Konrad had previously felt that home was an illusionary concept for a soldier to have and that finding peace when your job is to fight wars is admirable but impossible, death is the only line men like them can cross. Konrad finally admitting that Walker can go home is an encouragement on his part for Walker to prove him wrong, the best part being that Walker has that choice!
It also has a meta aspect to the heartwarming statement, considering so many people criticize this game by saying it hates the player and wants them to feel like a bad person. But in that, it reveals that no, it doesn't hate you; quite the opposite. All the game did was perhaps ask you some questions that you felt uncomfortable with when the answers were found, but in the end it's nothing you should dwell on too badly, since one way or the other, you can still go home...
In the epilogue Walker has one last choice: either let go of his gun and go home with the U.S Soldiers sent to rescue him, or become the villain he thought Konrad was and fire on them. It's up to him to decide whether going home is worth more than his fantasy. Should Walker make the first choice he says these simple words, "It's over. Time to go home." Walker has taken Konrad's words to heart, finally deciding to put down his gun and avoiding crossing the line. There is always a choice - and Walker finally made the right one, which is the choice to bring his mission to an end.
The name of the achievement you get for going home complements Walker's choice, fittingly titled, "The Road Back." Even sinners deserve to go back home, even after all Walker has done he still has the hope that he can return home if he will only make the choice to take the "road back home" as it were.
Even if it might be a hallucination Konrad praising Walker for his admirable — given the circumstances — actions in Kabul is very heartwarming. This scene establishes that the relationship Walker and Konrad had was professional and friendly, they were men that respected each other and conducted their duties as officers with passion and dedication, and how Walker looked up to the man and Konrad nurtured his younger counterpart. The tone of voice Konrad uses to address Walker sounds almost like a doting father figure, he speaks with warm kindness, and adds immediately after praising Walker that he didn't know if he had ever told Walker his feelings, sounds like a father who felt ashamed he hadn't told his son sooner how proud he was of him.
One intel item shows a conversation between the Radioman and Konrad. Konrad starts right off the bat by asking the former that he call him "John" instead of Colonel, requests that he not be recorded (of course, he is, via a recorder hidden in the Radioman's bag) and thanks the Radioman for being a friend and listening to him during these trying times. The Radioman thanks him awkwardly before going through his bag to turn off the recorder while claiming that his pen ran out of ink. End recording.
Listening to some of the Enemy Chatter moments really help to establish that these are not monsters but men that have friends and family and they are really only trying to make the best out of their dire situation; just like Walker. It takes on a tinge of tragedy because neither the 33rd or Walker should be fighting each other, as Americans they should be on the same side. Still it is amazing that just a few idle words about sight seeing or asking a buddy for a stick of gum can add so much humanity to what are otherwise faceless drones. Makes it all the more worse when you have to kill them.
One of the intel items has the Radio Man giving a personal monologue about why he decided to do his radio broadcast. He discusses how amazed he was by the people of Dubai getting up every day and continuing to live their lives despite the hell that surrounded them. Even more amazing was the revelation that despite their ordeals they still mustered up enough spirit to create art, an example of the tenacity of the human spirit. He then recalls Edward R. Murrow's broadcasts during the London Blitz in WWII, who proved that despite the Nazis being able to flatten our cities and our bodies there was nothing they could do to crush our spirit. In the same way the Radio Man felt that perhaps he could do a little bit of good by broadcasting, remind the citizens of Dubai that there is still hope and that adversity alone is not enough to flatten the human spirit.
One that literally lasts less than a second: at the end of chapter five, Walker kicks in a door in a dilapidated skyscraper, which unleashes an avalanche of sand, causing him to fall out of the building. Seeing this, Adams yells "Martin!" and tries to grab his hand. The fact that he addresses him as "Martin" rather than "Walker" or "Captain" shows that Adams really values him as a person and sees him as more than just his superior, and suggests what kind of leader he sees Walker as. That is, before all the horrible stuff starts happening.