Confused about the Flashback Timeline. [[HEAVY SPOILERS]]

First of all, yes. I've played Final Fantasy 7 and Rebirth before, so no worries about spoiling me about anything.

But I'm curious about something that doesn't add up, and I'm not sure I've missed anything.

Cloud tells the Team that when he arrived in Nibelheim, it was the last time he talked to his mother. And we all know that Cloud is remixing his memories with Zack's.

But them, it seems like a lot of days passes after Cloud/Zack and Sephiroth return from the reactor, Sephiroth starts reading like a possessed man and etc...

But what was Cloud (the real one, lol) doing all this time? Didn't he felt like visiting his mother at least once? Did he stay holed up in the hotel all this time?

Or it's simply a matter that from the start of the Climb to the Reactor, all of Cloud's memories are Zack?