It’s a good idea to be skeptical of this too. Not the sadness of anticipating missing friends who you love, but the predictions of how bad it’s going to be.
If you watch it closely, you’ll see that your mind is smuggling in anxieties and negative predictions together with legitimate concerns. Like someone sneaking bootlegged items past TSA or customs. Don’t let it get away with that.
It’s possible that the relationships will decrease in intimacy. It’s equally possible that you’ll become much more intentional about maintaining and even increasing intimacy in some of them because a) the distance requires you to be more intentional about the relationship, and b) the distance, paradoxically, gives you enough of a psychological comfort zone to feel like you can reach out without being overwhelmed by the response. On top of that, even if you see those friends less, you may enjoy the times much more because you’re no longer numbed out and oppressed by constantly coping with working at that company.
Anyway. I relate to your thinking style. My points and predictions will likely not be 100% accurate, but I’m just writing them down here to remind you that in predicting the future, there’s room for flexibility. An inflexible negative (or positive) prediction is often a give-away that you’re dealing with an emotional projection rather than a balanced assessment of likelihood.
Trust yourself. Your deep nature literally passionately wants to be happy. It’s going to motivate you to work to make that happen (as you’ve been doing). It might take a while, but those are some pretty powerful internal resources that are working toward that end.