Have you tried dropping tiers? I notice you are hovering at t8 or above(past 8k games with 29% survival). Perhaps try dropping to tier 5 or 6 and focus improving skills that yield wins rather than damage( which comes automatically if you do so). So, you would typically play tanks with the ability to flex to either flank/or just run to a safer spot to defend from. Examples: T37 forces you to provide your red teammates something to shoot at while surviving till end game, M4/Strv74/cromwell gives you the option of flexing to either flank when need be or just forcing your team through a position by flanking/exposing their defenders.
Higher tiers usually require really well skilled tank crews and operator with good equipment setups. Playing t5 forces you to hone skills + learn good spots/abuse vision for attack/defense on any map sans great crews or equipment etc as it's a total crap shoot most of the time. Once you can consistently sustain good stats at t5/6, try t8/t9 and you will notice a marked difference in your game play. Not t10 though, as solo play is not recommended ( I am your best example).
Pityfool's advice is great but only if you actually have the ability to analyse team comp, map needs and team skills within the first 30 seconds and can force your team follow through on your plan!