Choosing your battles wisely is a good start. I have never had many arguments with my ex's or the present relationship now for this reason. Is it so important to pick out every little detail of another person. I concentrate on their positive sides, and the good things they have to offer in life. There is no perfect person, so if you wanted too, you could stand there all day arguing and pulling someone apart. If that is your focus anyway.
If you are arguing over important things like money, shelter, food, bills, clothing and the necessities of life I can understand the importance of standing your ground. But perhaps the way you communicate in a positive or negative manner really effects the outcome. You don't need to yell, threaten, be little others to get your point across. But this is mainstream in our society we think we have to use force and be negative. It depends on your foundation you layed from the start as well. If you are both good communicators, open and honest, you will listen to each other and feel safe discussing things.
But if you choose the other path, you will be arguing all day to prove whose right and whose wrong.
You have to accept your differences and understand no matter how much you would like to change another person, you can't do it, nor fix them. Instead of focusing on what they are not doing, ask yourself what are you doing wrong. It's easy to say the other person is, but they are just a mirror of yourself. There is something to change about how you're percieving the moment, and you're belief system. You really have to step out of the box, and put yourself in their shoes.
Although we would like to judge others for what they are not doing, what is it that your doing? lol It all comes down to looking at yourself, and being a good rolemodel yourself in the realtionship. If you expect them to do all the changing, I'm sorry to tell you, it will never work, and you will keep arguing to the point there is no relationship left. Now the question is, how important is the relationship? How much time and effort are you going to invest in yourself and your part, and allow them to work on themselves?