Pretty much ALL contact is going to be unhealthy now because he's cheating..
That makes him prone to anxiety, aggression, paranoia, defensiveness, deception, etc...
THOSE habits he picks up when he starts a stressful and hurtful secret affair with OW...
When he talks to YOU, his impules drive any hope of a healthy convo into the toilet because hsi impulses are messed up (see above behaviours he picks up when affairs start)...
He is PRONE to destroy any healthy communication wtih you out of guilt and fear right now... he's in SELF DESTRUCT MODE...
He WILL take YOU AND YOUR KIDS WITH HIM when he calls.. he has no control over himself right now...
The ONLY way to END that unhealthy contact is to NOT pick up. THIS FORCES HIM to CHANGE what HE DOES...
This gets HIM moving out of that cycle AND you...
You are both digging your graves when you talk on that phone...
We really care about you and want this marriage saved.. so PLEASE dont' pick up.. or at this piont I would say give the phone AWAY... I don't think you can control yourself with it right now... give the phone away.