Mari is a bottom it's not like she's suffering not all bottoms wait to be attacked and pushed down some just go with the flow and do whatever to make the other happy if I could go back the the innocent days with my partner it would be like falling in love with her all over again just enjoying each others company and nothing else.
It's a nice idea to start thing all over, if things work themselves out just fine - still I think it can hurt to have your partner forget little things that matter to you. But even if it's the "same" person, it becomes a different story, somehow it looks like the start of a new relationship, meaning the end of the previous one which ended pretty abruptly; I find it a bit sad.
I'm not saying bottoms are helpless puppets who just wait for things to happen, just that in the case of Mari, it is possible that it confuses her a bit to be the one having to initiate (like she said in the first chapters). I didn't read up until chapter 14 when I wrote that post, but now it's even more apparent that it has been bothering her - the dynamic has changed, adaptations are to be made, so it's going to be somewhat stressful : our brain don't like change very much, after all.
Not necessarily true since we've already seen an instance of her recovering a tiny bit of her memories.
Well, since we are the sum of all our memories, somehow, Arisu(a?) will eventually become a different version of herself even if she regains some of her memories. If she regains all of it, I can't say for sure what that would make her. But since she has gone back to her three year younger self and Mari has grown up in the meantime, it's almost like they're starting a new relationship with two different individuals.
Mari already had a relationship and Arisa is starting her first relationship again. It's not going to be a drastic change, but it won't be exactly the same relationship is what I was trying to get at. The fact that Mari has to be the one initiating contact is already a testimony to that change.