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Habit stacking can help. They all stop eventually, some of their own accord, others with support. I know it is exhausting having to resettle so much but that is unlikely to be due to feeding to sleep. Even babies fed to sleep can sleep longer stretches, a lot of it is down the individual temperament of the baby. My son for example was fed to sleep, and even at 3 is not a great sleeper, on the other hand my 6 month old can now go stretches of a 4-5 hours overnight which he never did - she is also fed to sleep. She sucks her thumb at times, which comforts her and gets her longer stretches. I haven't done anything differently for them, they are just different in their sleep needs and i know it is likely my youngest will go through periods of frequent waking again at some point.
If it helps reassure you at all i have plenty of friend's and family who sleep trained and had babies who slept well but as toddlers their sleep has been bad with them needing more comfort and closeness, with many ending up bed sharing or getting uo multiple times a night as a result.
Another great resource is the Beyond Sleep Training Project, they have a website and Facebook group you can join and ask questions for advice and support. They also have a red flag guide you can use to make aure there is nothing that needs running by your GP/health visitor, sich as mouth breathing.
Could you set your bed up for safe co-sleeping through out the night? We have a standard sized cot side attached to our bed (side-car) which means we all get more sleep through safe bed sharing.
One great thing i read when i was in the thick of it is that 'dependence leads to independence', in that through meeting your babies needs, day & night, and them being dependent on you helps create confident, independent children and adults.