Why "if" was used here? It's not a conditional statement.
Native speaker’s answer
Rebecca
Rachel is only speaking the first half of a conditional sentence, and the rest is understood because she is conversing with someone. Her full intended sentence is something like "But if time was what you needed just to gain a little perspective, then you needed to take that time". This style of conversing expresses doubt, as she didn't believe Ross needed to take this time.