Call the court coordinator, get some dates to reschedule and give them to opposing counsel. Then get a rule 11 in writing from her and file it.
If you've got a motion for continuance in, generally you don't need an affidavit of why you need more counsel. Affidavits are only for hearings that don't require testimony.
If she's refused to agree to anything, you can still withdraw your child support and custody schedule and get in one you like more. A right of first refusal isn't far fetched in normal circumstances but if your access is limited to less than standard visitation, it might be pushing things a bit.
I would strongly recommend calling up a local family law attorney for help and consultation.
Generally, a motion for continuance requires an agreement with the opposition, OR an affidavit supporting the statements you make in your motion. Get your attorney soon.
I'm not your attorney; my answer to your question includes assumptions. If you want me to be your attorney, I'm easy to find.
You need to hire an attorney as soon as possible and let them deal with getting the continuance. Depending on how long the case has been pending a judge may not grant your request for continuance unless you have an agreement from the other side (and some judges do not even care if there is an agreement or not).