Hi Lin,
I'm not a "long-term" maintainer yet, I'm just at 2 and 1/2 years. I will have to say that I am in agreement with Jay and Glory when it comes down to how much harder it gets as time goes by. For me, it's very difficult to maintain, and to be honest, the only thing that keeps me going sometimes is facing other people. Seriously, I feel like if I gain weight, I'll terribly disappoint some of my major real-life supporter...(Oh, and the fact that I know it just gets under the skin of those nay-supports who never thought I could do it...<evil grin>.)
I just keep trucking every day. I still count calories, and I still weigh and measure things like meat, nuts and salad dressings. Over Christmas I kind of had a few sugar binders and struggles with cravings and that "wanting it so bad that I'm miserable" thing...so I'm trying my hand at low carbing plus calorie counting to help me get over the sugar cravings. (BTW, it has helped tremendously by the grace of God!!)
One thing that really kind of bummed me out was when I went to put on some winter clothes from the last couple years. Oh it was wonderful that they still fit nicely and all but that super "high" I had when I first got them, that awesome feeling that I LOOKED HOT in them, is gone. I wish I had the giddy feeling still, the "Hey look at me I'm a size 6" floating on air feeling. But that is long gone. It's just another job now. ugh. I hope to h*ll I can keep this up for life, but oh my gosh, it is super hard for me now that the newness has worn off.
ETA: I also agree with Fitmom...one blow out does not mean I've blown it. When I've gone astray, (so far) I have reeled it in quickly and forced myself into better choices ASAP...If I don't, I'll be back to 333 in no time.