Oh man, that sounds brutal!
I don't have the magic bullet I'm afraid, but here's what worked for us. I did the tie-yourself-in-a-pretzel-to-nurse-while-pottying-the-baby maneuver for a long time until she finally started holding it at night. I would clamp (important to clamp, otherwise bucket of pee all over the bed) our potty bowl between my thighs (I stored potty bowl in the co-sleeper since Lord knows my dd wasn't sleeping in there!), hold dd in a cradle hold with right arm under her neck and shoulders and left arm under her near leg and left hand holding her outside leg just above the knee. Latch her on and tuck that bootie deep down inside the potty bowl. Make noise and hope. After pee, wipe baby butt without unlatching, CAREFULLY put the potty bowl back into the co-sleeper (if you're super organized and baby is peeing multiple times a night it might be worth having a bucket to dump pee bowl into...I did this at my parents house when spilling the potty bowl would have been a BIG no no), and lie down without unlatching. Whew! It was a bit complicated but worked for us... Good luck!!!
