Cal can never get any respect from anyone despite saving the world. Then you realize everyone has had their memory erased of the event, including Stacy. They know about him saving the world second-hand but they weren't there to witness his courage, heroism, or genius. So, they just treat him like the second-stringer he is in their minds.
The Guardians lack of trust for Cal becomes a lot more understandable when you realize they think he went on a killing spree in his armor. When it was actually another man wearing his armor.
Cal is a murderer as well since he killed some of the squad sent after him in Secrets of a D-List Supervillain.
Cal doesn't like Paper Tiger, Wendy's new boyfriend despite the fact he has no interest in her himself. It becomes easy to realize why when you note he's a Nice Guy supportive boyfriend with no major personality dysfunctions in a Dysfunction JunctionRagtag Bunch of Misfits.
Cal sold a lot of advanced weapons to the Evil Overlord who proves to have been planning to mentally enslave everyone on the planet and is a Bad Boss who kills his employees without hesitation. Just how many innocent people were killed with Cal's weapons?
Lazarus mind-wiping Stacy didn't just erase her memory of her relationship with Cal. It also removed all of her progress as a person and growth in self-confidence as well as skill as a warrior. In effect, she Took a Level in Badass and he took it right back. She gets them back at the end of Confessions.
