Hi! Where did you get married? If you got married in the US, surely your estranged husband must've gotten a divorce there. But if you're married here in the Philippines, he might have not disclosed in the US that he was previously married or that he filed for divorce in the US to sever your marriage bond. In such a case, you may need to request a copy of the foreign divorce decree from your estranged or now former husband and have the same recognized in the Philippines.
However, recognition is not a simple matter of presenting a copy of your foreign divorce decree to a Philippine government office.
Recognition is a judicial process where both the foreign divorce and the foreign divorce law need to be proven in Court. You will need to file a Petition for Recognition of Foreign Divorce with the Regional Trial Court in the Philippines. You will need to get a lawyer to prepare and conduct the case.
What are the documents you should prepare?
1. Philippine marriage certificate/record if the marriage was in the country
2. Official marriage certificate/record from the foreign country if the marriage was abroad
3. Report of Marriage of a Filipino married abroad (if one was filed with the DFA)
4. Official copies of your foreign divorce documents
5. Certified copy of the foreign country’s divorce law
6. Proofs of citizenship
Note that this is a general list. Depending on the particular foreign country involved, and depending on the particular case, there may be other documents necessary. This is because different countries have different divorce processes and different kinds of marriage and divorce documents.
These documents can be merely scanned copies when you first send them to your lawyer. The value of having these documents is firstly that they allow your counsel a clear view of the circumstances. Reviewing them will also allow him to advise you of what other documents you may need to get.
However, these documents will eventually have to be presented to the Regional Trial Court with the Petition. For it to accept these documents, the Court needs to be assured that they are genuine.
The Philippine documents will need to have been officially certified by the correct government office (Civil Registrar/Philippines Statistics Authority/Department of Foreign Affairs/etc.)
The foreign documents, on the other hand, will need to be certified by the correct foreign office and they will need to be authenticated (Red Ribboned) by the Department of Foreign Affairs or the Philippine embassy in the foreign country. If a foreign document is not in English, then its certified English translation is also needed and this also has to be authenticated by the DFA.
I do find it necessary to mention that this opinion is solely based on the facts you have narrated and my appreciation of the same. Thus, the opinion may vary when the facts are changed or further elaborated. I hope that I was able to enlighten you on the matter.