Character stops attacking for no reason

I have my main attack set to Right click and I had a full mana flask yet in the middle of a breach I just stopped attacking. I could run around but none of my skills would trigger and then I died. This is not the first time this has happened resulting in my death and subsequent loss of XP. Wouldn't be so mad about it if I didn't lose the XP for a reason not of my own doing. Can we fix the inability to attack bug and also remove the loss of XP?