I don't believe it gets harder after each cycle. The AAS is nothing more than a tool. The things that help keep gains going are anything but your cycle. Your diet first and foremost. I'm sorry if this isn't what you want to hear but it's the truth. Eating a lot and eating clean is more important than any compound. Your training is also vital. You have to keep at it just as hard as when you're on cycle. If everything is in check in these two departments, you'll make gains on or off cycle. An aggressive pct is essential for a seamless transition. The most important thing is your motivation. If you want this and are dedicating yourself to this lifestyle, you won't have any problems in the gym post cycle. While you're on cycle the idea is to maximize gains and push yourself further than you think you can. Take full advantage of everything AAS offers. Train harder and eat bigger on cycle. You'll be fine. A lot of what you're talking about is mental.

Just come off my first cycle's PCT and dude I'm still loving the gym just as much, if you are happy with the way you look (IMO) you are fuelled in your workouts, pumps not as great and yeah I don't feel like the biggest guy at the gym anymore but i have kept my strength gains amazingly even without hitting the gym as much as I should (PCT blues) and I'm making gains slowly again but it was well worth it (Though I'm already preparing for my second cycle, in time of course.)