This is from ages ago but it seriously still sums up 5SOS.
CH took every media article and every troll on SM as being Taylor's fault. It wasn't Taylor attacking his song writing abilities, it was online trolls making fun of him so he went after Taylor instead of ignoring the things said online. The SM meltdowns, liking shady tweets, getting pictured with the Kartrashians, wearing the Yeezys, all of that was to humiliate Taylor the same way he felt humiliated from her "fans". That article was not an apology to her.