Letting go...

Recently my message has been to just let go, so, i have been letting go, a lot. Its hurting much more than i thought it would this time. I've let go of a former love, three friends, and now I'm about to let go of my real friend, but in a different aspect. She's just going back to college, still, there goes my source of strength. I'm just, so confused. Why would God ask me to let go of everything and everyone, when, now I'm just more down. I don't completely get how that works, but then again, who is able to get how God works?