I haven't posted here in a while, so "hi" to all!
OP, I lost between 40-50 lbs. (didn't have an initial weigh-in, so the best I can do is estimate). I've been maintaining for three years now. I stopped weighing myself several months ago because it was causing me to be anxious and I didn't want to live like that.
Over the past several months I've had to lower my daily maintenance calories by 100 per day because I noticed that I was was slowly gaining. I could tell by the fit of my clothes. I don't know whether my metabolism has slowed down, my body has gotten too used to my exercise routine (so more efficient & burning fewer calories), or I'm just less rigid with weighing and measuring (I suspect it's a combination of the last two reasons).
At this point, though, I still feel good about maintaining and am not panicking about the gain of probably under 10 lbs. After all, I can still wear all my clothes and my face looks better than it did at my lowest weight.
Like others, I've gone through some significant stresses: just had to put one of my dogs to sleep and the other, I'm afraid, will be shortly following him; this has been a major heartbreak for me as I do not have children, so my dogs are my "babies." As such, I'm still very proud of myself for staying on target with regular exercise and counting calories. I have not gone the route that I've frequently gone in the past of saying "to heck with it" and just eating anything and everything in sight. Could my eating be better? Definitely. But in evaluating my choices---more stringent eating/lower weight vs. looser eating/a bit higher weight---I chose the latter. The point is, though, that it was a conscious decision, and I do not feel as if I let go of the reins and was out of control. I think mindset defines maintenance success almost as much as the number on the scale.