If I signed my marriage certificate in my previous married last name, even though this wasn't my legal name, is it valid?

You were legally married and the marriage license is still valid.

Will I receive a monthly payment for life on the pension received during divorce?

It depends upon the pension plan. Hope you filed a QDRO?

How does one go about having changed a divorce date that got finaliazed without the knowledge of the respondent?

Were you not properly served? When did you find out that she filed?

Depends. Is there a Will granting a person powers to act? Is there a Trust?

Whatever was filed was rejected because it was not done properly/correctly.

Can you help me?

You need help from a probate attorney. Yes any one of us can help you but you may have created a mess that will need the services of an attorney.

How can i file a stipulation Judgement?

You prepare the right documents and file it. Go get help at the court house self help center and they can tell you what you need to get this done.

I am looking to retain a probate attorney. The attorney for administrator agreed to mediation of proceeds. Now he file 850 petit

Start by googling attorney's in your area. Do this now and in fact do it the very minute you get off AVVO.

What else will be in the process for disolution in my divorce in LA?

No I can't answer this. You have an attorney. Sit down with him/her to discuss what is going on.

In CA Superior Court how does a Plaintiff seek relief when he/she becomes mentally ill while aged, while civil suit is ongoing ?

This is now a probate matter. Someone needs to be appointed disabled Petitioner's Conservator of the Person and Estate in probate court. They can...