Falsification of Civil Wedding Requirements -- Marriage void?

At this point, I have learned a painful lesson that marriage is 90% of your happiness, in some sense.
I met my wife in a dating site and known her just a couple of months. She got pregnant and I married her to prove my sincerity.

We now have 2 children; 1 yr old and 5 month old. During the more than 1+ year that we are together, it came to my realization that the marriage is not happy anymore and having this sense of belief that my wife had the intention of getting a hold of my properties. We came from different backgrounds. I came from a poor family but worked hard to be at my position now and along the way invested on several real state properties prior to marriage (1 ongoing condo amortization). She does not have any property during our marriage.

I then realized that our civil wedding is that of conjugal property. What I knew prior to marriage is that all properties that I have invested in my name prior to marriage is mine. Her sister is a lawyer and she always insist that she will take part in my property everytime we have quarrel. I just felt this is very unfair given the situation. Philosophically, she don't deserve anything that i have invested upon with the way she treats me and my family.

Now, we're contemplating on separating or annulling. I'm looking for grounds to nullify her explicit demand of gaining half of any property that i had prior to our marriage. I had to research wedding requirements, wherein her mother did all the processing. Her mother was able to bypass or probably falsified the Certificate of Attendance since I never had the chance to have the pre-marriage counseling in which I could thought about doing prenuptial prior to agreeing to the default conjugal property.

Here are my questions;

1. Do i have a ground for nullifying the marriage if i can prove that her mother falsified the requirements needed for Civil Wedding?

2. Im the only one working and supporting our family. What rights do i have when it comes to custody of our children? I read about <7 yrs should be with the mother, but is it possible to contend with this if the mother is not financially capable to raise the child on her own? How would this relate to the child support that she may ask from me?

3. I'm planning to file for separation of properties. If she don't agree, do i have ground to proceed to file?

4. Regarding the ongoing condo property amortization, if we annul now for example, how will the ownership of the condo? does it need to be completed? how about the equity?

1. check the requisites of marriage under the family code.

2. you should have shared custody. if you want sole custody, you will have to request this through court and prove that you have valid grounds in doing so.

3. if you have valid grounds then regardless if she agrees, you can proceed.

4. the property will be split. you can buy your wife's share or vice versa or you can also just sell the rights and split the money.

thank you for the informative response!

I just like to follow up on your answer in #1. I already researched on the requirements of civil wedding and one of them is the "Certificate of Attendance" which i believe is being falsified by her mother to proceed with the civil wedding.

Do you concur that this is indeed a requirement and is a ground for voiding the marriage?

hard to say since to prove this, you have to incriminate other people which definitely they will counter your claims.

would it be true that regardless of how you came around getting a marriage license, whether through falsification of some required documents, is still a marriage license?

as far as the law is concerned, it is implied that the requirements are obtained in a legal way. you have to prove it otherwise in court if you want to invalidate a legal document.