I swear if by "a little more time" she means more than a chapter, imma flip some tables.
Like so many inexperienced people, Liao seems to think that dating is an all-or-nothing proposition: you are either friends, or you spend every second with each other having kinky BDSM sex in furry costumes 24/7. It does not occur to her that a romantic relationships between adults involve highly non-linear negotiations of boundaries, just like every other relationship with adults she has navigated thus far in her life...
I think she's more worried that a relationship breakup could be scarring enough to make returning as friends impossible. That's a reasonable and pretty common worry. It's just a bit overused in these types of stories but I guess for good reason.
Yeah, breakups can be real bad, but my point is that if you two are adults with functioning frontal lobes, ease into the relationship little by little to see how much you're comfortable with, and understand that if one doesn't feel comfortable, you pull back a step and stay at that level of intimacy. Again, Liao's problem is that she sees dating and breaking up as 0s and 1s, whereas it's really a continuum. In fact, I think that Pei Yu actually understands that, so it's really all on Liao's insecurities in this case.