I feel a lot of people are just missing something obvious about Lena's reaction concerning Holly/Ian.
She's jealous. Of Ian. Because she wants Holly too. She might not be ready to admit it to herself yet tho. Of course she's a lil hypocrite. Guess what ? Most humans are. Combined her jealousy with her insecurities (is Ian another Axel ? Is he gonna crush her trust and feelings yet again ?) and you get her reaction to that story. Regardless of her own flaws. You can't expect someone to be totally rational straight away, it's highly unusual in those situations. She might come around in the next updates.
I'm pretty sure it's something that has to happen to get the Holly Trinity anyway. Some kind of fallout, some action with Holly, then at some point something or someone pointing out how hypocritical she has been with that situation.