Forget the cyber sex. Forget the real sex. If the child is being left alone on the premises at all, the question is not should you seek full custody. The question is why haven't you already sought temporary custody via an emergency petition pending a full custody hearing. Irrespective of whether she sleeps around, or sings soprano in a church choir ans slips out for song practice, leaving the child alone is a significant issue. Get counsel and address this sooner rather than later. If you can not afford counsel, try to find a pro bono referral or Legal Aid or just run it yourself, but the time to act would be now, not sometime in the future.
Answered on May 10th, 2013 at 6:18 AM