It sounds like you've never been married. It's not a matter of getting the government to approve, it's a matter of getting other people to recognize it. If you have a common-law marriage but it's not documented then if your spouse falls ill and taken to hospital you might be denied visitation rights, for example.
I suggest you read some court filings/legal articles on the gay marriage cases from a few years ago to get an understanding of why people sued to have the right to get legally married, over and above just having an emotional commitment.
I suggest you read some court filings/legal articles on the gay marriage cases from a few years ago to get an understanding of why people sued to have the right to get legally married, over and above just having an emotional commitment.