Panel 1: Now that he's home, we find Mike trying to make sense of the fact that he can't relate to Martha as a real person the only way he knows how: writing pretentious bilge in Lynn Johnston's handwriting. He starts by wondering how one can describe the pain of longing before describing it as only a goofy teenage GIRL fixated on the forever and ever love of the week can.
Panel 2: He can't describe the hollowness and emptiness that is his state of being and how hearing Martha's name makes the mask of acceptance slip off and reveal the vapid dolt within.
Panel 3: He then observes that since his self-induced pain makes him a 'better' writer, he thinks that wallowing in misery is the key to being good at bad writing.
Panel 4: He then wonders if it's possible to be both famous and happy.
Summary: Eventually, he'll think that mechanically shoveling shit onto the page makes him a good writer. He'll still be wrong.