Is it okay if while my mother is here, my ex-spouse comes in a bit while the door and window are open? If he does this while my mother is here and it’s not permitted, would this require me to get another get?
We live in basement level, have a wrap around courtyard, and are attached to another family (elderly man and his helper) living next door. Most of the time we left door and window open. Someone can see in the home somewhat from the street level but not all the way in the house.
Your ex husband should not be coming into your apartment at all, even if it wouldn’t be yichud. For your husband to enter your apartment would cause a potential yichud situation, even if your mother is with you, as yichud between one man and two women is also considered yichud.
Kiddushin 80b, E:H 22-5, 119-8,9,.