He didn't even wish me a happy birthday?

My ex and I broke up 6 months ago.

We got back in contact 3 weeks ago had some drinks talked a lot on the phone, but this week he didn't contact me at all no calls no messages nothing he knows it's my birtday today 100% so it's not like he forget or anything I'm sure of that

how could you be so cruel not even sending a text it really hurts me should I confront him about not talking to me, and forget my birthday on purpose what's the reason of someone doing that
He didn't even wish me a happy birthday?
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