I moved to a new country a year ago. I did have a couple people saying goodbye but for the most part it was pretty lonely feeling. My ex spouse who I'd been with for nearly 13 years and have maintained a good friendship with since divorce was one of the ones that didn't really say goodbye, that hurts still. I think it was too difficult for them to confront that we will very likely never see each other again. I don't know your friends but it could be some of them are feeling similarly, maybe some don't realize the importance, or even there could be people thinking you have support so their contribution isn't impactful while not seeing that a bunch of people doing that creates a bigger void
I would reach out to some of them again and tell them it is important to you that you do something with them specifically. Be open. Asking once might not have conveyed what you need and they may not realize the importance and gravity of being there for you
As far as getting through it moving is really difficult. Look forward to what you can do at your new place and try to train yourself to not get lost in the past. It's easier said than done I still struggle with it despite having done this a lot. It's important though. You can take your growth and everything you've learned and work towards what you want and need more efficiently but you need to be pointing forward to go anywhere