Hi T.,
I know exactly what you are talking about. I'm not sure if it has something to do with being 8, but my daughter went through the same fears at that age. Simple things like watering the plants on the porch just outside the playroom, or going to the step to get the paper without her would make her completely panicked. We never really did get to the bottom of what started the fear in the first place, but there had been talk on her bus about "hobos" that were "living" in a wooded area near school. The stories on the bus got out of control and we finally heard about it directly from her. Although we explained that the term "hobo" simply referred to a homeless person and not to a "deranged murderer" (as was the talk on the bus), it didn't seem to help much. We tried to stay away from talk about that and just address her fears in general.
My advice would be that you should do your very best not to lose your temper or get frustrated with the situation. (It drove me completely nuts!!) At times I would get frustrated that she couldn't explain why she felt the need to be glued to my side at all times, and I would raise my voice to her when I finally reached the end of my rope. All that did was to make her even more panicked. She feared that if she wasn't with me at all times that I might get fed up with her behavior and "sneak out of the house" without her!!
Her dad and I gently pointed out that we had never yet done such a thing, and that we never would. We talked about how it was important for her to have her independence from us and for each person to have their own "space." Our house isn't huge and if the dog wasn't under my feet, she was! Without coddling, we encouraged her to keep a timer with her and let us go and do something quickly (i.e., grab the paper) and agreed on the amount of time we would be gone (5 minutes). Then we would come back to make sure she felt OK, and would wait a short while and tell her we were going to go and take care of something else and would be back in X number of minutes. Little by little, we would increase the time and we would praise her when she wouldn't panic. One example was to bring a bag of garbage out to the garage and then come back in. Then, go back to the garage and walk one trash can to the curb and come back in, and then repeat the process with the recycling can. I also gave her one of my necklaces with a cross on it (could be anything) and whenever she was feeling anxious, she could hold it and rub it and try to calm herself down. I also gave her one of my shirts and let her wear it over her pjs each night and it gave her a sense of my presence. As she gained confidence, I would tell her that we would play a game or read a book together just as soon as I was able to sort and put in a load of laundry alone, or pay some bills at my desk, or something that took a little longer than 5 or 10 minutes to do. She would use her timer and I would check my watch to be sure I followed through. If it was going to take longer, I would touch base with her and let her know that I needed a bit more time.
For a long time she didn't want to go to sleep unless we were on the same floor (again, our house isn't big!). She wanted us to promise that we wouldn't sit out on the deck after she went to bed. We told her if she would feel better, we could keep the baby monitor in her room so she could call to us if she suddenly felt the need to. After a few times of responding right away, she knew she could depend on it and it helped her to calm herself enough to sleep. It helped to keep her favorite music on low in her room at bedtime so her thoughts wouldn't be racing.
We never belittled her for being afraid because everyone is afraid of something at some time in their life. We tried to be as encouraging as possible and to acknowledge each successful effort in independence. Eventually, she was pointing out to us her successes, and the fears slowly faded away.
Is it easy -- NO!! Will being patient get you where you want to be more quickly than losing your temper with her?...Abosolutely!! She is now 11 and is a big help with her little sister (who is 8!) I often hear her tell her sister that she "was afraid of lots of things that really weren't scary" when she was her age. ;o)
I hope this is helpful and I wish you the very best!
L.