Having experience in this field with my parent's 2 divorces each, I'd give you the advice I've had to live by.
Both your parents love you. They always will, and despite their mistakes, they will continue to want what is best for you. From what I can tell, your parents are having a hard time in their marriage, whether about money, personal issues, etc. If it doesn't blow over, I would recommend that they get a divorce simply to avoid these types of situations again. If they know it or not, they are hurting you by arguing and by causing you this much stress, and you'll feel this for the rest of your life.
Your dad seems to be the parent that you've clung on to, which is usual. I've found myself favoring my dad throughout my life, however, I love both my parents. Your mother is, understandably, incredibly hurt by this. Not only is her husband and the father of her child either pulling away or being pushed away from her, but now her own child is emotionally pulling away as-well. The extreme amounts of stress that this causes can be incredibly damaging to her self-esteem and her emotions, which because she is only human, may not be expressed in the best way possible.
My experience with divorce has caused me to grow up a bit faster than those I go to school with, and I hope what little information I could provide to you can give you a better understanding of how this all works. Show both your parents love, force them to sit down and talk about what is going to be best for you, whether their separation or counseling would be better. I really feel for ya, kid. I wish you the best.