"completely crushed" They've only been seeing each other 4 months! He's a fully grown adult man, not a lovestruck teenager.
He could have behaved like a decent person and said thank you for your condolences. That's what normal people do. Instead, he chose to be aggressive and put the phone down on her.
How people behave when you say NO to them shows exactly who they really are.
And in the 4 months they were seeing each other, he was moving very suspiciously fast. ANY guy that says the following shit so early in the relationship should be dumped, because this NEVER bodes well for the woman:
"In the past 4 months all he went on about is how I now have the best version of him and would say I promise I will look after you forever... a guy who said he loved me more than anything and wanted to spend the rest of his life with me"
And he's also a deadbeat dad.
And he clearly doesn't give a crap about anyone but himself:
"the day of our first date my sister passed away suddenly that morning, we weren't really close but it was a shock and yet another funeral i had to arrange , i messaged him that morning and said im going to have to cancel this evening as my brother has called to say my sister passed away. He did know my sister and all I got back was a message saying no problem . No sorry for your loss or nothing , 3 days later he messaged to say hope your ok and im thinking of you"
Sympathy should be reserved for OP, not this red flag wannabe cocklodger.