You may have post-traumatic stress disorder (PTSD). I'm sure many of us here have it. There are specific treatments for it so you could try asking your IC about it. My feeling a few months after my husband left was like I was living a nightmare and I couldn't wake up. I just couldn't believe it was real. There are few who can understand this level of pain except those who've experienced it. It requires a new level of patience and endurance to get through this.
