I disagree. Based on what she said when bedding MC for the first time, it seems she herself had been a virgin up to that point. She popped her own v-card to try and get him to stay, for Jaye. That's a bit more than basic friendship in my book.
I think that's effectively backwards. Tara clearly
wanted to sleep with the MC, the issue is that she knew her BFF *also* wanted to sleep with him. Trying to persuade the MC to stay allowed Tara to kill both birds with a single, err, bee.
The whole situation definitely shows that Tara cares about Jaye a lot, because she was willing to subordinate her own desires to protect Jaye's feelings. But it's in no way an indication she
loves Jaye. Her statement that there's nothing romantic between her and Jaye may be exaggerated, but it seems clear to me that her primary feelings for Jaye are platonic. That's why her overriding drive seems to be to hook the two of them up so they can finally see if things work or flame out.
Ceteris paribus, I think Tara would much rather date the MC than Jaye.