Thank you for your question. I look forward to working with you to provide you the information you are seeking for educational purposes only.
It would have, at the time, been grounds to file a motion to have the judge remove himself from the case for the appearance of bias or impropriety had you raised the issue at the time. However, once you accepted and signed the guilty plea knowing this judge was connected to your prior divorce without raising the objection to the judge handling your case, I am afraid it in most cases it is too late to try to undo the plea agreement
You have a very slim chance here, but you do have a chance, and that is to file a motion to vacate plea and you will need to have medical documentation attesting to your mental health condition and you were not capable at the time you signed that plea to understand the nature of what you were doing. Whether or not you can get the court
to vacate the plea will depend on the strength of your medical expert testimony about your mental condition at the time of the plea. This is not something that is done frequently, but it is the only option that is now available to you within the year from when you signed the plea.
You need to get a local attorney to represent you on this after you get a medical expert to agree to testify that you were not mentally competent to agree to the plea.
As far as the judge, as I said, you had grounds at the time to remove him from the case and you would have to argue he should no longer be involved in your motion and that you did not object at the time because of your lack of mental capacity at the time to do so.