first off, you are doing great! it's really gutsy to show your pic like that, too. "love yourself, at whatever shape you're in", imho, is easier said then done; i suffered for years from poor body self-image. you have come a long way in the past year or so and your story is an inspiration that we can all be motivated by to be the best we can be, and really live life.
anyway, i definitely agree with above posters in that the body needs change and challenge. otherwise the efficiency will stay the same, most likely.
this is why, in addition to practicing yoga, i also use weights, run, do martial arts, and walk (i.e. extra walking, as opposed to everyday regular walking). basically i change up my routine so that my body is always guessing. i recommend you try some other activities, too. main thing: have fun! otherwise it will be hard to come back to it. and you can alter your routines slightly to challenge yourself and get more results.
yoga: you could do poses longer or deeper (which may be hard if you are in a group class but can be easier if you practice alone or take private lessons); weights: it means either using heavier weights or increasing the amount of sets or reps each workout, week, month; running: going further each time or faster...
this is why it can be advantageous to document what you do to chart your course. then when you hit the peak of what you can do, start a totally new workout. for me, that keeps it interesting for me mentally and physically. personally, i don't periodize my yoga, i do that more with weights and running. when i practice yoga, i just let how i feel physically, mentally and emotionally right then and there dictate how and where i am going; it can be many things which i usually don't find out til i get there... it can be a spiritual experience, a therapy of sorts, an altered state, an escape, a retreat, and or communion with my self, Self, and others. sure it is physical, too, that is the gateway to inside. but, imho, the physical asanas (poses and movements) are part of but not the whole of yoga.
in any event, all the physical stuff be it asanas, weights, running, etc. that's only one half of the whole enchilada (some may even say 10% or less). i remember a personal trainer (can't remember exactly who though) saying that even though working out and being active plays a part in tone and definition, the real contributing factor is what we are eating. . you can workout like a maniac but if you eat like a maniac and your bf% is high, there will be little definition. look at the strongman competitions or football linemen.
if you can can get your bodyfat down to a lower percentage than it is now than you will see how much muscularity you have. sure if you build muscle that will boost your metabolism and you'll be burning calories even while you sleep... but imho there is no substitute for a) reducing caloric input or b) reducing caloric input while increasing caloric output.
imagine wearing a sweatshirt or a heavy coat and pants. well how can you tell what's underneath?
you can only guess, unless you strip down to a t-shirt or spandex.
no one can or will say it's easy though; it takes patience, persistence, consistence, dedication, and will power. i think the trick is to not eat less volume food but less calorically dense foods and also to go with a slight decrease as opposed to a drastic amount of calories cut. don't forget to make sure that you keep your blood sugar at normal, too.
anyway that's my 2 cents, hope it is insightful and helpful for you; it actually has made me realize that my diet (calories input) is the hole in my game, so to speak. as one poster mentioned above 1-2 bad snacks can undo whatever caloric burn you accomplished.
i have worked out like a crazy person over the past 10 years (i just love the high from it) and eaten whatever i wanted to in any amount and although i did drop and keep off about 50 lbs i wasn't disciplined enough to get past the plateau because of it. after being mindful and aware of my eating input i have now got down 10-15lbs and kept that off and i'm inching up to the summit losing my footing every so often but at this time unable to get to the peak. which is my goal. it's really an undertaking and i'd imagine it is for other people who tend to be heavy due to genetics, metabolic type, and or a voracious appetite and love of food (most of the members of this forum?).
this is why it's dangerous to dramatically cut calories or forbid foods because you may set yourself up for overeating.
alright well i'm going to hit the hay, namaste