Yes and can be quite alot aswell. you need to try some cruise lines like fred olsen or try to find one that is cheaper then the suppliment does not feel so bad - it is all worth it.
Yes. I paid £2000+ recently with Princess (Caribbean) but it was worth it. I am 76 and sharing is not comfortable now although in the past I was happy to share. Breakfast can be taken in the cabin at any time and all in all one can call room service when you want. Also if ill it is ideal.