Westy said it before I could, but then, she's been instructing for a lot longer. I disagree with 28th. We all have days when we want to jack it in, and wonder why we ever started. And if you leave the airfield feeling that way, it can last. I felt like that at various times during my PPL, definitely during my CPL, and most especially during and soon after my instructors course!!!!! I honestly wondered if doing that had put me off flying for ever. But all if took was getting up there with a student to realise just how much FUN it was and always had been and always would be. So go up there for a fun flight, look at the view, and remind yourself of what the rest of your life could be like.