How does one climb if you are only a few divisions below where you should be? Please help me...

I get that diamond / master / challenger players climb consistently every single season on smurfs, but what is someone who isn't so extremely far beyond their opponent supposed to do to win more games? I am SOMEWHAT better than the enemy team in every game I play, they always make stupid mistakes and I try to take advantage of them, but I'm not a challenger player, I just don't have that insane combination of every skill honed to perfection that would allow me to win every game despite my team ignoring everything I say and making poor decisions despite my attempts.

I put in dozens of hours of research, I practice every champion that I play in ranked til at LEAST 30k mastery before I take it in, and whenever I lose a game against a matchup, I watch a video of how to lane against that matchup. I read articles about macro strategy and when to make what calls, but nothing comes of it because in the end, this is a team game, and I need to be able to rely on my team to follow up when I make a call that I know is the right one. But people just don't trust each other, I get flamed for pushing lanes to take towers, or trying to force baron / dragon when I KNOW with EVERY FIBER of my being that it's the right call. I get flamed for a great engage because my team doesn't follow up, even though I know we win the fight because its a 5v4 and their most fed player is splitpushing, and they just used major cooldowns, and our ADC just hit a power spike. I make the call, I engage, and nobody comes, and I get blamed for inting.

So what do I do? How can I climb? I just don't understand it. I'm sure if I were a god at this game I would have no problem reaching Gold V (my goal), but I'm not. I assume I just BARELY belong in Gold, because I have played plenty of games against plat / diamond players in normals and held my own just fine, but when it comes time for ranked the following pattern happens every single time:

1. I get a few godly games in a row where my team wins the game without me having to do anything.
2. I get promoted.
3. Every game after I get promoted is a one-sided stomp where no matter how hard I try, I'll win lane and make good calls, the enemy team just completely steamrolls the rest of the map then spends the rest of the game shutting me down, while my team completely ignores every ping and every politely worded call I make.
4. I get demoted.
5. Rinse and repeat, ad infinitum.

I want to climb, I know what people say I need to do to climb, and I try to do it, but it just doesn't work, because I am not so ridiculously far beyond my opponent's in knowledge and skill that I can 1v9 every single game. Sure, I can make picks and capitalize on some of their mistakes, but eventually the weight comes crashing down and I just can't bear it alone anymore. I don't know what to do. I try to snowball other lanes, I push towers and ping for dragon / baron when it's smart to do so (enemy jungler and 2 others just died in a fight at 30 mins, let's baron team!) but no, we get a few good picks and the team just shoves a single wave, goes to farm jungle camps, recalls, whatever else besides the smart play to make, and I can't do everything alone.

Then, after I get demoted, I get a bunch of awesome teams in a row: coordinated, communicative, we all win lane and run over the entire map.

Then I get promoted and the inting happens again. It's not just coincidence, this has happened like 5 times in a row. Promoted with good teams, then a bunch of inting teams, then demoted.

Is there something about matchmaking that says "ok you just got demoted and we don't want you to feel bad so we'll give you a game where the enemy is lower mmr than you so you can have a few free wins" then when you get promoted the game says "ok now you got promoted so we're going to give you a team with lower mmr than your opponents and see if you can solo carry every game until you get demoted again".

Is the game trying to keep me from climbing? It really feels like things are stacked against me, and I am extremely frustrated and becoming mentally exhausted from pushing myself so hard every game and getting no results for it because someone else on the team doesn't feel like putting in the same amount of effort I'm putting in.

/end rant