I was in your shoes - co sleeping with a permanently latched, sucking baby. It was getting progressively worse from 4 months (we decided to make changes at ~8 months as I was bordering on complete insomnia and a breakdown). I couldn’t bring myself to do any form of unsupported crying but I knew we needed to make changes. You need your OH’s support and commitment, without it I think you’ll struggle as you are the breastfeeding parent and it’s what your child has come to expect. We have two bedrooms and currently I sleep in one room with a monitor while dad sleeps in another with DS’ cot in there (attached to the bed).
Firstly, get your day routine/schedule absolutely nailed down. Have wake up, naps, bedtime and solid food within set half an hour windows and don’t deviate.
I personally wouldn’t pack in breastfeeding. Firstly, this isn’t a breastfeeding problem, it’s a sleep problem. Breastfeeding is both fantastic nutrition and a wonderful comforting tool and taking that away from DS at the same time as altering sleep would likely end in a very very distressed baby. Offer breast +++ in between food and naps during the day.
We started by OH consistently settling DS in the cot for his first nap for a week or two, to get DS used to sleep = dad. We chose this nap as it’s relatively easy to achieve and it still leaves another nap if it goes pear shaped. My OH used a shh pat method and lots of cuddles/reassurance. Despite this, there were tears for a couple of days. I took DS out in the pushchair every afternoon to ensure he had a good nap. After a few weeks I took over and did both naps in the cot. Prepare for an overtired baby at this point for a while as they adjust - we still don’t consistently have long naps now.
We then went nuclear with night times. One night we just changed and OH took DS into the spare room and settled him in the cot in there. Again, lots of cuddles and shh patting to start with. There were lots of tears - maybe half an hours worth? Next night it was ten minutes then it stopped. OH never left DS side. We were firm. If DS woke before midnight he wouldn’t have a feed - OH would settle DS, even if he was very upset. Anything after that he would have a feed. Within a week DS was down to one wake at night and actually we didn’t have any middle of the night hysterical episodes.
A lot of people will tell you to fully night wean. I personally wouldn’t in an 8 month old. DS wakes now at about 3 or 4am and he actually appears to be genuinely hungry. If I feed him he goes right back down and sleeps through until 6 or 6:30. If I don’t feed him we start the day at 4:30 or 5 with a crying hungry baby. There is a difference between your baby being reliant on boob to sleep and also respecting the fact that a lot of babies cannot go 11 or 12h without a feed, no matter what some may tell you.
Our next step is to try all of this away from dad in the nursery. I’m expecting this to be the hardest step yet, I mean it might just be now that his sleep prop is my husband’s presence, not boob - we might even go back to hourly wake ups, who knows. But currently this is the best sleep as a family we have ever had.
I hope this has been some help x