Broken, you will get through this but it won't be easy and there will be 2 steps forward and 1 step back at times. It's ok. Just keep trying to do what you know is right. I remember when I was in therapy and I told her that I felt "guilty" going to buy myself fresh vegetables at the market. She was like "WHY?!" I said it's because they're sitting in their cars with hardly any food (I paid for food, gas, their used cars, cigarettes..you name it). I constantly felt like I should punish myself from any kind of joy (even buying fresh vegies) and should always remain in a state of mourning over their situations. I felt like I should not be happy if they weren't. She said, feeling guilty means you've done something wrong and she told me I most certainly hadn't.
Don't get me wrong, I still hurt when they hurt (as most of us parents do) but I have learned I am not responsible for anyone else's happiness. My sons are not responsible for mine either but by keeping myself in a state of mourning on their dire situation, I felt like it gave me some control or something...which is certainly didn't.
Getting through this is a full time job and requires a good support system. But it's all possible because when you realize it's YOU that needs to change, well that's something attainable.