So, let's make a rule.
If you like someone, and you tell them how you feel, and they are honest with you and tell you that they don't return the feeling, here's where we're at...
(1) You have the right to be disappointed
(2) You have the right to be sad
(3) You DO NOT have the right to be angry
(4) You DO NOT have the right to make that person feel like they are at fault.
It's nobody's fault. You can't help who you are attracted to, and conversely who you are not.
Now, if they're a jerk to you when they tell you this, I guess you'd have the right to be angry. Not for the message, but for the method.
Had this happen to me recently. Someone asked me out. I didn't know how to tell them I wasn't interested, so I accepted, but finally got up the nerve to admit that I had been wrong. I didn't mean to toy with anybody's feelings, but I suppose he may have seen it that way.
I've never been on the other end of it. I've had overwhelming crushes on people, but they were dating someone, or they weren't interested in someone of my gender, or I just knew due to their personality/the context of our relationship that I'd have been denied. So rather than risk it, I curled into a little protective porcupine ball - soft center hidden, scary spikes sticking out.
Dude, there's a reason I'm alone.
That reason is me.