It's a issue of sanity...after a few months of studying I needed a bit of flying to remind myself why I was doing it all.
I took a break half way through the groundschool to go and pick up another 70hrs and then came back and blasted the last few exams.
I would definitely go flying - you need to build quite a few hours - try and build it into your programme to fly regularly - remember some will drop out due to weather. If you have free weekends, they will vanish repidly as the workload increases, unless you come up with a plan now to fly every fortnight or so.
Another vital bit - grab an instructor and ask him/her to give you some challenging exercises for your hour building, with a view to your CPL/IR. It's no use poddling around on some easy stuff - you need to work hard and hone skills - it'll be much more enjoyable that way.
Try not to compartmentalise flying - studing - training etc etc - otherwise this will become a job too soon and you'll lose the fun in the hard slog.
Good luck and enjoy.