My own experience (a year further on than you) is that the flying seems more stressful irrespective of how often you fly because you are in that period where you start to realise that the PPL was just the start. I doubt you really are less proficient now - you are probably just more aware of any deficiencies. Reading the posts on here emphasises how much there is still to learn and experience.
For me, I found it very rewarding to do some flying with other non-instructor pilots as well as solo trips.
Before we got the PPL, we all heard everyone say it was just the start, but its not until you actually start flying 'for real' that the true meaning of this sinks in.
On the other hand, for those who took up flying because its absorbing, this is part of the fun. It's the learning curve which keeps it absorbing.