
I believe that cutting IC ties in such a situation is fine.Â
Whether you retcon or not is your choice, it's your right. If you're on the fence about retconning, however -- consider how the having the elements of the other person's story meshed with yours makes you feel. If the memory of them, or things associated with them make you uncomfortable or just irritate you, a retcon may serve you well. If it doesn't bother you so long as you no longer need to interact with the person again, it may do no harm to keep their character in the background story of yours!