Boyfriend disappeared for weeks ( HELP!!!)

So my LDR boyfriend of 1 year disappeared on me for 3 weeks and just contacted me back 4 days ago with just a "Hi" (no explanation at all, as to where he's been). I didn't want to message him back because I feel as if he's trying to manipulate me. I had contacted him last month before he just randomly disappeared on me. We are both busy people but would never go a week without letting the other know what's been happening. If it does happen, we always apologize. I admit I did disappear on him for a week once because I had lost 2 family members. But I did message him and apologize. I don't really tell my BF a lot about my family/ life in general because he doesn't seem to care. That's why...when I go through these emotional times, I never tell him.

What I meant about manipulating is that he will go 2 or 3 days without contact and just appear....then say he's been busy with work. I have been understanding of this but even when I call, he'll ignore my calls and say that he was busy. It got to the point where I just stopped caring and that's when I noticed he started to contact me more (calling and texting more often). 

Now I don't know what to do. I really need some advice ladies!! Should I contact him or just disappear and never ever contact him??!!

He's already hurt me emotionally and I'm scared of getting hurt again. I need realistic advice please!! 

Also when I noticed it had already been a week without no contact from him, I just assumed that he met someone else....so I just let it be. Was this my fault?!