Years ago I had a client who had been in a car accident. She came to me for energy healing - and I actually saw the entity!! It wasn't super scary or anything, more just like a lost, wandering thing looking for an energy source. Since she'd been in the accident, which was traumatic for her, it opened a space for the entity to latch on.
How she was experiencing this attachment was simply that she was listless, distracted, and lacked enthusiasm - and this was all so NOT her normal behavior.
During the energy healing session, together we cleared it, and helped it move on to the next plane of existence for it.
Over the days that followed, she regained her enthusiasm and vibrancy again!
So entity attachment does happen, and sometimes not in the most obvious of ways.
Have you ever experienced anything like this, or known someone who has?