I've been through the having no confidence thing and come out the other side now.
I went through a stage of not riding Joy, paying someone else to school her 3 times a week and returned to a RS for lessons to get my confidence back.
Now I think I'm on top of it but despite having had loads of hacks and gallops, I still get the occasional 'I can't go this' twinge and have to remind myself that we are through it now. Once self confidence goes it takes longer to build up again.