It's very strange that a domestic abuse case would be prosecuted without a witness. And essentially that's what's happening - because you're refusing to press charges. So .. did someone else see the assault? If not, it's unlikely that the case will hold up.
Someone else will have to speak to the IMM1000 and whether a return to Canada would be affected by an assault conviction.
No one has witnessed what exactly going on. However, the officer took pictures of some minor scratch marks. Anyway my wife had a medical condition and she is being treated for. Thanks