i still don't think you are correct in thinking that the problem is this city, and that people in toronto are just more shallow than in other places. like all metropolitans, people living in them tend to be more well-off, and thus have the funds to invest in their outer appearance, be it through fashion, nutrition, exercise, and just general well-being in terms of mental and physical health. and the more people have invested in their own appearances, the higher their expectations are when it comes to their choice in romantic partners. other cities aren't any different. you might be relying on some anecdotal experiences, but that doesn't mean it's true generally, or that your luck in toronto won't differ compared to other places you've been. it seems like you're just trying to write off toronto so you can give up more easily on your chances of finding love. that's not the right answer.
based on your comments, i really believe it's your outlook that needs to change above all else. you seem a bit depressed, and you might benefit from some psychotherapy before anything else. you do seem to have a defeatist attitude as someone else said. just because you're in your late 30s doesn't mean all is bleak, or that you're running out of time. this is especially so since you're a man, and society doesn't place such a high value on your youth as it does for women. i knew a guy who at 28 had finally quit smoking and drinking, started to hit the gym, his sex drive had skyrocketed for the first time since puberty, and was really looking forward to his 40s when he knew he would be finally established in his career and income. it's really never too late, and you need to remember this. lots of young women i know are really into older men - i went through that phase myself. we all want to be that little coquettish nymph seducing the DILF and having all his attention. you can be that guy too if you wanted to be. at least fat is something temporary, unlike facial features or some other permanent physical trait.
i think you need to try not to fear loneliness as much as you seem to, and learn to embrace your solitude. learning to enjoy being alone is something valuable i think every person needs. spend some time getting to know yourself and your passions. people who know themselves well probably have an easier time finding what they want in life because they know what that is. you talk about women in terms of 7s and 8s, but do those numbers have any real meaning to you? you don't want a barbie, but you still seem to insist on being with a conventionally attractive woman. that's not necessarily unrealistic, but at the same time, it sounds like you're needlessly narrowing your choices down, ironically in a rather shallow way. that isn't the way to go about finding happiness in your romantic relationships at all. a good partner should surprise you in ways you hadn't expected. the image of the perfect 7 or 8 in your mind could be non-existent for all you know. for me, when i think about the guy i want, i always begin with personality traits (independent free thinker, dry sense of humour, appreciation for the arts, good knowledge of underground subcultures) before moving onto physical traits. physical traits like attractiveness and being fashionable are nice and all, but incompatible personalities are always going to be the dealbreaker, especially if you're looking for a life partner, which it sounds like you are.
you need to come to realize that just because you're overweight doesn't mean you need to settle for the first ok looking woman that comes along. you need to ask yourself about the kinds of qualities in a person that makes you happy, and narrow in on those traits when getting to know women. i know that when i'm getting to know a guy, the first thing i'm looking for is whether this guy knows what he wants in life. confidence begins with knowing oneself.
while you're spending time learning about yourself and challenging yourself mentally, start thinking about ways to challenge yourself physically. you don't need to start today. considering your injuries, what are some ways you can get some movement into your lifestyle that are realistic? someone mentioned swimming, which i personally love so much. i love being in the water and it's very easy on your joints. i'd also recommend biking - we have some great cycling routes in this city, especially the lanes along lake shore. you can even just take more walks - downtown toronto is always exciting and beautiful and there's always something going on. just walking for a half hour or an hour a day can really get you looking fit - you'd be surprised. just remind yourself that a 30 min walk is always better than no walk at all.
during the winter, it's easy to get bummed out and just hate everything around you and want to give up. we've all been there. now like i said, you don't need to go and start launching into a gym and diet routine tomorrow. but maybe start slow and work little things into your daily routine that pushes you in that direction. cook a healthy meal for yourself that you enjoy. there are so many recipes online for free. use the resources available to you. cut down on alcohol, if you happen to drink a lot. cut down on high carb, high fat meals, which can make you sleepy and more sedentary.
stop thinking about your life in terms of a timeline, or thinking you are running out of time. we could all die tomorrow. your life happens day by day. and every day is a chance to make a change.
oh and finally, i think your fears of ending up with a superficial partner are unfounded. it sounds like you might not have ever experienced true love before, but i'm going to tell you that when you do fall in love, it will take a lot more than just a few extra pounds here and there to break up that relationship. so fret not about this now. you need to better yourself for yourself, first and foremost. forget everyone else. your mental health and your physical health are inextricably linked. nurture one and the other will follow.
i know it must feel frustrating to feel invisible due to your weight. but there are big people out there who get a lot of respect from others for reasons beyond what they look like. and i think cultivating those good personality traits always begins with self-acceptance and self-love. until you learn how to love yourself, you won't be able to nurture your body and your health the way you need. once you're able to do that, love will find its way to you in unexpected ways.