Just wanted to say I was in a similar sort of position re wondering whether or not to wean. I've only just gone back to work - DD3 was a smidge over 12 months and her solids eating is far more miss than hit too. I feed her around 5.30-6am and then not again until 7.30 pm when I'm home and she's about to go to bed. I do find she usually has an extra feed that night, but she seems pretty happy with it and Mum (who she stays with while I'm working) has said she's been fine and is drinking a fair bit of water throughout the day.

ETA: Sorry - just saw your post about the D-MER. If she is taking water from a sipping cup can you try mixing formula and/or cow's (or any other kind) milk in slowly with her water until you build up the amount? I really don't think you need to worry about her starving. Good luck.