First off, thank you all for the advice, including the negative comments. I genuinely may not haven taken it seriously enough or thought enough about the future. I didn't post back, but I read through it and considered many of the suggestions and most turned out to make a lot of sense.
I spent a few weekends just running through most of the ground school, planning diversions etc. or reviewing notes during my lunch breaks. For the practical part I just tried to run the whole flight in my head about once every 2 days or so.
Fortunately, the company required me back at the end of May, giving me the opportunity to shorten the gap considerably this time. I figured I'd try to do a mock with my last examiner first, but it would prevent him from doing a test with me later, so my main instructor came up with another solution, allowing me to do a full mock with a very experienced instructor who I had not flown with before. It did help as he made me look at some things slightly differently. It was small things such as different ways to do track corrections, but it really helped. After that, I mostly ended up doing PFL's and glide approaches, solo or two-up. It's obviously two things you don't get a do-over on and I really wanted to consistently be able to hit what I was aiming for.
So finally I did the second test yesterday (the aborted attempt in April was never really started or recorded as a test). It was all going very well up until diversion, when I rushed it a bit and got my track wrong; a quick eyeballing showed me my mistake, so I was able to correct it and arrived at destination. I partly forgot a Hell check between stalls, but apart from that the upper air work went well. And on the PFL I would have ended up nicely in my chosen field. Finally the circuits, where I had to deal with a decent crosswind. It went fine, apart from occasionally drifting a few knots over the ideal approach speed. On the glide approach I ended up a bit far down the runway, but it was acceptable.
After shutdown, the examiner shakes my hand and tells me I've passed. I could feel tears in my eyes and a huge sense of relief. I was finally out of purgatory.
The debrief was very useful. It confirmed some of what I know, I occasionally still chase the instruments too much and I will need to work on achieving greater accuracy. But my decision making had improved considerably, I was able to spot my mistakes early and correct them. There is still a long way to go, but clearing this first major hurdle gives me more choices to improve.
It became very hard towards the end, and I would agree with some of the comments in saying my instructors should have been more demanding. I felt I was not really learning very much from flying with them anymore. On the other hand, they were trying their best to allow for my difficult schedule and part of the problem may have been I just wasn't committed enough.
So now I need to find a way to keep it all as current as possible and be very mindful of safety if I have longer spells without flying.