Yes, @stomachcramps. Your H is an entitled, self-serving cheat who has been conducting an emotional affair with his new cyber playmate. Besides the flattery and ego-boosting, there will have been a sexual component with explicit exchanges/videos.
His abandonment of his vulnerable child and you, his devoted Wife who has given him an abundance of deep love and support — to pursue this superficial infatuation with a stranger — is truly appalling and sickening.
I assume that H will rendezvous with OW during the upcoming trip, having reported to her that he is now separated. As he is currently in thrall to her and is trashing DS’s well-being, I wouldn’t put it past him to introduce DS to her as a ‘friend’ and perhaps include her children on an outing. If so, that plan needs to be blown out of the water pronto.
If the solicitor advises a legal remedy to eject him from the home, I would follow that path. After nuking the marriage/family, how dare he throw you into a torturous limbo waiting for him to leave at his convenience. I figure he is currently hedging his bets. If his test drive this weekend is disappointing or if things in Paradise soon go sideways, he’ll attempt to slither back to you. He needs to be permanently gone asap.
@stomachcramps, you are clearly a fierce and fantastic mother who is completely in sync with what your precious boy needs to feel safe, so he can soar. You and he will help each other navigate this trauma, moving from strength to strength. Perhaps a children’s counselor can provide support. Your H will live to regret his destructive choices, but it will be too late.