Hi Juno
My recollections of my PPL training were similar to yours .... although I think I was doing a solo at around the point you are at now, possibly slightly sooner.
I was also only flying every other week or so, even took an 18 month break in the middle due to money constraints. It is perfectly possible with average ability to progress at this pace.
As soon as you get the solo out of the way, then it all starts to get more interesting with the Navexs etc, so I would suggest that when you speak to the CFI you find out how they think you are progressing towards the first solo. Maybe suggest that they tailor a few lessons with a small navex to another airfield to do circuits there or something similar ... to keep the interest up.
Also type of aircraft flown can be important. I seem to recall I could nail a low wing aircraft in the circuit really easily but put me in a cessna and I was all over the place, maybe even worth trying an hour in a different aircraft if for nothing else other than a change. This might be frowned upon as not the quickest way to achieve a solo, but if it gets you past the boredom bit to the interesting stuff then a couple of extra hours on the course wont be wasted.
Keep it up .... nipping over to Le Touquet for lunch makes it worthwhile ;-)