The fact of the matter is, there is barely even a handful of champions in the game that are viable without flash. Examples being, Shaco, Hecarim, Renekton, and Shyvana. I can't really think of any other champions, so if you think of one, let me know.
Because flash is necessary for almost every champion to be viable as it is by far the most overpowered summoner spell with a near infinite amount of possible utility, you really need it if you want to perform well.
Take a look at your match history - you literally never pick flash. Mordekaiser 4-12 without flash. And I thought Morde was easy to gank to begin with. TF with no Flash OR Ghost. No mobility on an immobile, easy to counter mage. Karthus with no flash. The list goes on.
I would love having you on the enemy team because it would basically be a free win for me. Anytime my flash is up (or even just any time in general) when you're out of position there's no way for you to escape, so I would just make a play on you and kill you, and you'd feed (like you do often ranging from 1-7 to 4-12 ish scores).
I mean, you can either try to be all special and different playing "your own way" and complain when people point out your mistakes... OR you can try to understand the game at a higher level and make smarter strategic choices. Your decision. If being stuck in Gold 5 and feeding there appeals to you, go right ahead, but don't make it other people's problem.