It's only normal to fight a lot early in a marriage when people are too young to be married, did not know themselves or each other well enough before getting married, and possibly had some "unrealistic expectations" of what marriage would be like.
When two people want the same thing. (Each other to be happy)
there is very little to fight about. Marriage is more about US & WE and less about YOU & ME. It's more about finding a compromise as oppose to winning a battle. A couple having a lot of fights usually means one person is trying to get the other person to "change" in some way. We get frustrated with them for not changing and they feel resentment towards us for asking them to change.
Marriage is best when you find someone who (already is) what you want in spouse. It's a challenge trying to "fit square pegs into round holes" or "changing water into wine". Opposites attract in the short run but like attracts like for the long run. Both people have to want the same things most of the time in order to stand a chance of lasting "until death do us part."
Ultimately we're all looking for someone who will love, appreciate, and accept us for who we are.