Before Lup left to hide the Phoenix Fire Gauntlet, she said goodbye to Barry. Maybe it was something small, a last quiet “I love you” and a kiss on the cheek while he was sleeping. Or maybe it was something bigger: maybe she took pieces of the best day she gave to him and brought them back. Left a fresh-cooked plate of breakfast on the bedside table, intending to be back before it cooled.

I don’t think Taako got a goodbye.

Because Taako - Taako would have known, because Taako knows Lup better than he knows himself. The moment she acted out of the ordinary he would have asked, and Taako doesn’t care about many people, but for the people he loves he would do anything Lup is absolutely at the top of that list and she knows it.  

He would have realized it was a goodbye, and he would have tried to stop her. Or worse, he would try to come with her. So she saves her farewell for after she’s gone - and by that point, of course, he does not fare well at all. 

Barry gets his goodbye. Taako never did.