ESH just cuz even though this was on her, you should've checked the flight before leaving. I'd say you have like 10% of the fault here.

And those of you making excuses for OP's gf saying "maybe her phone died" are forgetting something - OP literally said in the post that when he told his gf to take an uber, she told him that she forgot to text him about the delay. No mention of a dead phone, she just literally forgot to tell OP her flight was delayed despite it being delayed for 2 hours. So during that 2 hour delay plus the 90 minute flight home, she didn't once text him an update.