A word on internal conflict: those things that privately affect the main character are the internal conflict. In keeping with my referencing the posts of the last three Wednesdays, his inner conflict could be: JAWS: inner demons (fears and what ifs), TWISTER: the past, ZOMBIES: survival guilt, coping with the changes in society and self, depression.
Inner conflict creates depth in the character and empathy in the reader. Visit some psychology webpages. Poke around a bit. The ideas and possibilities are endless. You just have to find something that feels realistic for your character, and which has an arc you can work with across the arc of your novel. If it contrasts or compares to the theme in some way, all the better.
So...for a starting point ask these questions and see if there are any applicable answers for your story, then go mining for more.
1.) What is privately at stake for your antagonist and how can you use that to force him into the fray?
2.) What is it that your hero is in the position to learn that would make a difference to or effect only his or her own life? For good or bad?
3.) What has he or she already sacrificed to keep the peace or be happy in their personal life in your story? How do they feel about it and how does that increase the internal conflict for your viewpoint character(s)?