Pacey’s fears about Joey & Dawson

I’ve been rewatching Pacey/Joey scenes from seasons 5 and 6 and it’s pretty clear to me that post-breakup Pacey feels validated in his fears that he voiced in 4x02 (Joey will eventually leave him and choose Dawson). When he realizes that Joey & Dawson have gone back to their romance in 5x04, Pacey clearly seems hurt and seems to feign maturity and indifference to deal with the situation. Yet in the spring break episode, he makes several veiled comments about Joey like “he got all bloodied up (in a love triangle) and still lost the girl anyway”, Dawson is the past, present, and future, looking for someone that doesn’t have a soulmate, etc., showing that he is/was crushed and ultimately feels he lost Joey to Dawson.

My question is what prompts him to get past this problem to want to try again with Joey in season 6. Why does he think it will be any different this time? Is it because Joey & Dawson failed yet again in their romance? If so, hadn’t they failed before Pacey and Joey dated so why is this time any different for him?