Some people hold grudges about seemingly petty things. Ignore list is the first step for such a situation, and its good that you already did that. If I were you, I would send a PM politely asking him to stop. Don't be argumentative, just tell him that you understand his difference in opinion, but accusing you of cheating is not welcome in your games.
Missing turns and getting double armies is not cheating. You can quote me on that if it helps.
Some people think of it as "abuse" of the game, and therefore its an okay reason for negative feedback, but in-game harassment is not good. I would imagine this will subside, because people grow out of their grudges. If it continues to bother you, post here again.