It is very easy to come up for a reason for Doves current behavior. As the demon Trigons power increases in our dimension (Raven using her powers empowers him) the lord of Order grows less able to influence his minions while the lord of Chaos is able to exert a stronger one. Dove having spent so much time with Hawk is easily susceptible to Chaos trying to take over. Dove unaware of the increased influence of Chaos on her psych, performs acts that her normal self would never do. This leaves Dove in the clear once the current situation is resolved. If they were the shows main characters you could easily go into the conflict she is experiencing as she becomes ever more violent due to Chaos influence.
Yeah, no. Nothing can make a Dove change. Freaking Black Lanterns can't effect either Dove. Nothing can effect Dove like that, period. Its bullshit made by people who either weren't aware of what the Titans were before they were hired to write that shit or don't give a shit about the material and just want more grim and gritty trash.