You're only somebody's bitch if you see yourself that way, and choose to act that way.
There was a time when the support didn't do anything, but spend all their money on wards; that was awhile ago for sure, but outside of it they really have had much more control over what they do.
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supports have a lane partner and generally have much more say in how the lane plays out early game than what adcs do.
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supports generally bring the cc/utility to your team and can heavily affect how your team does in the midgame with roams
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supports bring engage/disengage and can often instigate fights (and of course the good support will instigate the fights favorable to your team and therefore have an impact on the game) often enough by baiting.
if your adc has that little cs, then abandon them to help somebody more promising looking on your team. mute them if you don't want to hear their bitching- they are bad. Any good adc will expect their support to roam.
Often times I get annoyed when a support stands by me thinking I need to be baby sat 24/7 soaking up xp that could be solo xp while the enemy support is midlane making plays.
Find your win condition and overall strategy, sometimes change it accordingly. If you can be somewhere else without your adc automatically dieing or being zoned with the wave frozen then chances are it's better to be somewhere else (if your lane has been uneventful).
Other times you might be able to snowball your own lane and it'd be better to stay and being perma pushed botlane.
You make your own choices and impact the game how you see fit, don't blame your adc for all of your problems it's old as hell and is annoying how people fall into this victim mentality for no reason. Just ignore bad adcs