Hi Combakkid and welcome,
You have come to the right place. You will find so many understanding people here that can help you figure things out.
It's great that you had that "light bulb moment". I remember when I had mine. It all just started to make sense to me. You now recognize that there is a problem in your marriage and that it a great start. From now on it is a turning point for you. You deserve better in a marriage. You deserve to be treated with respect and supported instead of criticized. You deserve to be happy. One way or another you will get there.
Codependent no more is a great book. It really puts persepctive on things. The key to feeling better is to stop putting the focus on HIM and start putting it on YOU. He is who he is and nothing you say or do will change that. You only have control over yourself.
So knowing that, start doing things that make YOU happy. I started by exercising and eating healthier. I joined my neighbor in a zumba class and found I loved it! It's now my source of stress relief 2-3 times of week. I too felt very alone. I have 2 kids and no really close friends just lots of aquaintences. Build your support system. You have already started by posting here. I have made a big effort to be more social. Accept more invitations to do things. I am shy by nature so this was a tough one for me. When I really took a good look at things I saw how I was the one isolating myself by avoiding alot of people and things more than I should have been. Al-anon is also a great support if you can get to a meeting. If you cant, there are online, phone, chat and even facebook al-anon groups to start. These wont replace face to face meeting but can defintely be a support in the meantime. Good luck. You may feel confused and lost right now but slowly things will start to become clearer for you. Feel free to post anytime.