Welcome to the real world of marriage. It's probably got to do with compromising on some issues. I think that when you are living together there is no fear of being legally bound and one can always leave the other on a moments notice.
Now all of a sudden you realize that, although it's still an option, it is a lot harder to do. Was your spouse given an ultimatum to marry you? If so, there may be some bitterness there.
There are so many reasons why newly married couples fight that you could write a book about it. It may just be the newlywed jitters that are fraying your nerves. Remember, just because you lived together for ten years you still are newly married.
You need to look at why you got married and spoiled a seemingly "good" relationship. Are there some in-law issues? Stepchildren? Overall, what you are experiencing is very normal and if you are both commited to making it work, you'll just have to work out the issues and differences that make either one of you unique in your own special way. And remember, don't ever think that you can change the other spouse to be more to your liking.
For a marriage to work you also both need your own time away from each other so that you can enjoy each other when you do meet again.
And, perhaps you will fight for some time, until you get accustomed to being married - it's a major change.
I have been with my soulmate for 16 years, we recently married last year - this has happened to us (with mock fights)- My husband and I are "in love" with each other so we have nothing to worry about.
Your fighting now is merely a transition stage....but, conflict inevitably arises in any type of relationship and, if handled properly, it can strengthen a relationship. As long as it doesn't lead to abuse, things can work out.
The website below offers solid information to help with conflicts and outlines ground rules and step by step procedures on "fair fighting" - hope this helps you.
Fighting Fair to Resolve Conflict
Please take care - my best to you and your husband.
Peace, Love & Happiness,
The Mystic Wave