This is really starting to affect my motivation now, I feel like I've wasted an inordinate amount of time and money in recent months for what has been very little progress through no fault of my own, and there's no current indication of when I might actually get somewhere...
I know your frustration, but it's a side effect of the hobby we enjoy. I waited for about 6 weeks to get the right combination of plane availability, examiner and weather and that was for IMC renewal which by virture doesnt need as much good weather as does a skills test. I waited about 2 months for my FAA Biannial flight review renewal as well. If your in full time work elsewhere, and you have to compete with others for aircraft, examiners, and slot times, then there will invariably be delays.
Even when you have passed, you will have frustrations, but its better to be in that position, than not be a pilot and get to experience all the wonderful aspects of it :-)