Also, having feelings for someone who has been a huge part of your life isn't sick. It's OK to be sad and miss him. It's ok to feel anything you're feeling. You have to give yourself a chance.
I'm around here a lot, I'll let you into a secret. Some evenings (I'm in the UK, it's 9pm here) I go very quiet and don't post at all. Know why? Because I'm in pain, I'm missing my ex, I'm on the phone to my sponsor talking it all out- sometimes for 2-3 hours, that woman can seriously talk! I left him almost eight months ago. I'm only maybe a quarter way into dealing with all the **** left behind from our relationship. Noone's perfect, you just have to keep going forward. Sometimes I pause or slow down but as long as I'm not going backwards, it's ok.