The EU can't mend ties with China without giving up on Ukraine as China's FM Wang Yi has stated [0] on multiple occasions [1]. Additionally, in the Chinese foreign policy space, the EU is viewed as weak [2], and largely through the lense of the US-China rivalry (which is how the US views the EU as well now).
[0] - https://www.scmp.com/news/china/diplomacy/article/3316875/ch...
[1] - https://www.reuters.com/world/china/china-russia-discuss-ukr...
[2] - https://fddi.fudan.edu.cn/_t2515/57/f8/c21257a743416/page.ht...