IDK how I even found this because im not a UK fan and it's a few pages back but I just wanted to jump on and agree with you!
I have only ever seen colby get called out for the ross stuff and his relationship troubles, but never how bad he has been to bella.
I have been rewatching a lot of their old stuff since bella left here in aus (she is the only character i care about since alex left but as if nobody knew that) and the way that he has treated her right since the beginning really upsets me. In an old episode way, way back when simone was bella's support teacher she offered colby the number of a counsellor for her and he got incredibly defensive and refused multiple times without asking simone why she suggested it or asking bella if she wanted the counselling. ever since i saw that i have really began to despise him. I have a real hate for people that deny others mental health care.
Also, the amount of times since then that bella made it clear to colby and co. that she was struggling either via actions or words and they did nothing, even after she overdosed really gets me mad. IDK how it played out properly without gaps because of christmas and covid over here (you guys would have a better view point on this) but it wan't that long after her attempted overdose that colby said that he was done caring for her but the thing that really gets me, and i didn't realise it because of our covid break was that after he said he wasn't going to care for her anymore it was barely 2 in-universe weeks before she hurt herself, at which point he said that he had no idea that she was still struggling and that she had seemed happy. Like, as if that doesn't give the clear message that he barely cares for her at all.
I get that they are young but aren't they supposed to be around 25/mid to late 20's? because im in my early 20's and pretty much everyone I know would be able to figure out when someone they are around is struggling, especially when they are as explicit as bella has been. and colby is a cop so he should have had at least some mental health training.