It seems to me like you are pressuring her to stay. For example, what does this mean:

"It's been made clear having space from one another isn't an excuse to start seeing other people for a short while"

It's been made clear? Who made what clear? You "made it clear" to her? It sounds like you are trying to dictate how the relationship is going to run. It is not teamwork, a partnership, between the two of you. You aren't acting like her friend, you're acting like her boss. I feel like I am being harsh telling you this, but I appreciate you asking me for an explanation.

Maybe a better way to put it is, I feel like she is saying things, but since they are things you don't agree with, you tell her she doesn't have a strong enough "reason" to say them. That's called "invalidation", you can do a search for that word on PC.

But full disclosure, I am not in a relationship. But I just really think you can do better than her, be happier than you would be with her, someone who would suit you better, and appreciate you more, without you having to point it out to her. Seriously. You deserve better.