Wondered if anyone had dealt with this sort of thing before.
Pony is normally a star, hacks past most things without an issue although lacks confidence at times. Has also done some novice dressage and showing. I have hacked this pony in heavy traffic and also hacked lots of groups varying from 1-6 horses and she behaved very well in walk,trot and canter.
However she can not be ridden around strange horses without loosing the plot. She will pass fields of horses although is nervous but if one starts galloping around she gets very panicked and tries to shoot forwards,bucking rearing squealing etc.
If we meet horses hacking she will pass them excitably but will have a bucking/rearing tantrum if we see a horse hacking who is going faster than walk. God help us if one comes up behind at any speed.
She also does not like other horses (even friends) working fast when she isn't, for example if a friends horse is jumping and I'm asking her to stand it will cause a huge tantrum.
She is a very mareish squealy ears back type of horse. She is not friendly in the field with others either so it's not just a ridden problem. She isn't excited she is more frightened I would say.
It's becoming an issue as I would like to do some local fun rides or even cubbing but the pony goes into meltdown at the sight of a horse she does not know so it is limiting us massively right now 
Any ideas would be great, I know I need to get her out as much as possible but the thought of a group ride is a bit scary as I know how she will react!