What are your ideas for how the romance story between these three played out during the 20-25 year period inbetween the two issues (I personally am going right in the middle and saying it was a 22 year time skip). Carl and Lydia were still officially dating during the time of issue 192 but in issue 193 Carl and Sophia were very happily married. And seemed to have been married for quite awhile by that point.
For me what I am going to say is that undoubtedly Carl went through a very traumatic event when Rick died and it likely caused him to grow up a lot sooner than he would have otherwise. Sophia was always the person Carl went to talk to while Lydia was pretty much just the one to have fun with. Sophia likely would have been a far better support system for Carl while he was dealing with that tragedy than Lydia would have been.
Carl and Sophia would have really grown a lot closer in the months following Rick's death because of that while Lydia and he would have become a little more distant. Carl and Lydia would have still been having daily sex for a while still but it would have started becoming a little less important to him because Lydia wouldn't have been offering a whole lot other than that. He would have started seeking out the company of Sophia more and more until it got to the point to where he started preferring being around Sophia more than Lydia. I'd say Carl and Lydia would have split up for good a few months after Rick's death and then him and Sophia would have started hanging out as much as they could.
Carl and Sophia wouldn't have started dating right away though and would have continued to just be very good friends for a little while. However probably a few months after that they would officially start dating themselves. I'd say a year after Rick's death Carl and Sophia would have become virtually inseparable. They would have dated for a couple/few years and would have officially gotten married by the time they were 18/19. I feel like issue 193 gives an impression that Carl and Sophia had been married for a very long time by then so that is why I am going with them getting married by the time they were in their late teens. An easy explanation for how they could only have a six year old if they had been married for close to twenty years by the time of issue 193 is that they held off on having kids until they knew they were in a totally safe situation.