What cannot be changed, needs to be endured. Please look at the positives, not just the negatives. Just think how lovely it will be to be in the same building as your daughter, in the future, any time you are not too well she will on the spot to help hyou, provide meals, etc. Also, providing childcare, so much easier in their own home, without you having to go out.
Join the local U3A, etc and make new friends. New chapter in your life, make the most of it. Smaller place, much easier for housework, maybe some nice n ew iems of furniture. Not sure why you think your bills are likely to be higher. Surely, you are only paying your percentage, a fifth if I am correct i thinking there is daughter, SiL and rwo g.children living in this property.