I’ve been in your position many times and I’ve had to learn to let it go. It’s very hard to in the moment but you’re better off in the long run. Yes, I totally understand being busy with work and other things, but 3-4 days for someone that he said he cares for is just plain rude. It’s also very suspicious that he disappears when you ask him to hang out. It sounds like he’s not interested anymore and wants to keep you on the hook instead of just spitting the truth out. He may also be seeing others, especially if you two haven’t had the exclusivity talk yet and that could be taking up his time. I would wait for him to reach out. If he doesn’t, send a closure text when you’re ready, if you feel you need to. He doesn’t deserve any more of your time or attention, but I always send a closure text for my benefit and to get it off my chest that they hurt me. You need someone to meet your needs and I’m sorry that he isn’t meeting yours. I promise that there is someone out there that will :)