Maybe, maybe not. The problem with soloing her is outlasting it. Even though he got her down to half, he only got to the easy half of the boss, shadow and smoke. Once you step into the Ice and blood section of the boss things will get ALOT harder solo. Even if you do manage to get past ice and blood healing her, you still have to deal with soul split at the end, which could prove lethal since you are already low on supplies. SS will not onlt heal her, but drain your prayer too. So solo is not about not being able to survive her hits, but outlast her healing. Duo may be possible, but I don't solo will ever be possible. At least not with any of the current equipment in game. what she/he said right now, you just can't carry enough resources to kill her on your own