How old are your puppies? I also have sibling pups-a boy and a girl; they are 16 weeks old. There are times I feel quite overwhelmed with both of them and wonder "what was I thinking??"
, but like you said- I could never choose just one to keep. I know if I did get rid of one I would NEVER forgive myself! Right now they are like human babies, very time consuming with little positive progress being seen, but it will get better.
I keep my babies corralled in the kitchen area where potty accidents are easy to clean up. I don't let them in the family room until later in the evening when the rest of the family is in there to help supervise them. If they had the run of the whole house I know it would just be too much for one person to handle!! Right now they are not allowed in any rooms except the kitchen/dining room and the family room (sometimes). There are rooms of my house they haven't seen yet and won't be seeing for a while!
I also take them outside to potty often- at least every hour. I don't let them play, just do their business, then back inside. Then I know they are good to go for a while!
I feel your pain...
Hang in there! It will get better!