Yes, Percy turned down immortality for her, but so did Annabeth when she decided not to join the Huntresses.
Yes, Annabeth drove herself insane searching for Percy after he was taken by Hera, but Percy snuck out and forcibly invited himself on a quest to free Artemis just so he could find Annabeth.
Yes, Percy imagined Annabeth as the one thing keeping him tethered to mortality in the River Styx. She is his Achilles Heel, but she only found that out after she took a knife for him knowing that he was functionally immortal. He is her Achilles Heel too.
Yes, Annabeth saved Percy after his insecurities got the better of him and Circe nearly turned him into a guinea pig forever. Yes, she hugged him afterwards and said she was glad he wasn't dead. But shortly afterwards, Percy saved Annabeth from being dashed against the rocks and eaten alive because of her hubris. He held her and hugged her gently as she sobbed into his shoulder, realising that none of it was real.
Yes, Percy decided to plunge into Tartarus with her, but Annabeth used every last heaving, dying breath to keep him alive and constantly negotiate his safety. They both look out for one another.
Yes, Annabeth frequently mentions how Percy will be a great dad one day. Percy also once watched Sadie Kane jump in a puddle and wondered if this is what his and Annabeth's future kid would be like, before backtracking because it's not like he's been thinking about him and Annabeth having kids one day-
Yes, Percy is constantly monologuing about how cute Annabeth's bedhead looks and how lucky he is to have such a smart girlfriend. But Annabeth was once asked about Percy in an interview and complimented his bravery and general intellect Despite how oblivious he can be sometimes, and- no, that doesn't refer to anything in specific, it's just- he is so smart, but can never take a hint, even when a girl is giving him hints and- what? No! Why does everyone always think that I- that I'm- Augh! And forcibly ended the interview cause she physically couldn't keep her feelings hidden.
They are both down horrendous.
