Take a break and see other people. The two of you probably need it anyways. After seeing other people, you will know if you really want to go back to her...or if she wants to go back to you. Maybe she is also dissatisfied but is too afraid to say anything as well.

Another thing, you are comfortable and what is comfortable is not always best. You are afraid to take a chance and try something new, which is really sad because you are missing out on so many possibilities.

Your situation is also not very unique, many people feel this way so you are not alone in it. My friend impregnated his older girlfriend when he was just 17 and now they are married with two children, he is comfortable but unhappy and they go from hot to cold all the time. It makes me sad to see him like this because I know we could have been good together. He finally realized that after it was much too late for us.