Ok, Ive been married to my husband for 14 years, by common law. We have no marriage license, only done our taxes together. We live in Texas, we have 5 kids, we are separated, I do not want to ever go back to him. Do I need to get divorced or can I annul the marriage?

You may have what Texas calls an "informal" marriage. Therefore you need nothing formal to end it.

Texas: calls it an "informal marriage," rather than a common-law marriage. Under § 2.401 of the Texas Family Code, an informal marriage can be established either by declaration (registering at the county courthouse without having a ceremony), or by meeting a three-prong test showing evidence of (1) an agreement to be married; (2) cohabitation in Texas; and (3) representation to others that the parties are married. A 1995 update adds an evidentiary presumption that there was no marriage if no suit for proof of marriage is filed within two years of the date the parties separated and ceased living together.
See: Common Law Marriage (http://www.ncsl.org/issues-research/human-services/common-law-marriage.aspx)

Ok so who do I have to contact to get more info? And thank you

I gave you a link to the code section involved. If you need clarification contact a local attorney.

But it appears you staisfyt 2 of the 3 prongs. You cohabitated and represented to others as married (filing joint tax returns). Don't know about the agreement though. But therefore, you have to do nothing formal to sever an informal union.

One thing to consider is that if you have 5 kids you probably want (and need) child support payments from him. I think that will require a formal divorce proceeding - otherwise the court has no power to force him to pay support. As ScottGem says - contact an attorney.

Thank u

I gave you a link to the code section involved. If you need clarification contact a local attorney.

But it appears you staisfyt 2 of the 3 prongs. You cohabitated and represented to others as married (filing joint tax returns). Don't know about the agreement though. But therefore, you have to do nothing formal to sever an informal union.

The link ScottGem found is very informative. But it is not clear whether all three prongs, or just two out of three, have to be satisfied. I suspect looking at the referenced statute would clear that up

As ebaines has noted, OP should go to court to get a child support order. She should also ask for child custody. But I don't think she needs to file for divorce to do that. She can ask for custody & CS whether they are married. In other words (unless there is significant property to be divided), it's six of one and a half dozen of the other.

Oh, and to answer the original question: normally anullment isn't available when there are children of the marriage.