Your trust in him had already eroded before you found the text message; you were looking at his work phone because he was probably showing the classic 'red flags' of a cheater. Someone who is cheating often will not stop gaslighting their partner until the partner finds and puts some cold hard evidence on the table--evidence which you've found. If this was a mistakenly sent text, he would be suprised, confused or curious, not angry at you.
If the message is about an incident that happened, Read the message are if you think it is a mad person's description, he/she/they is/are mad.
Angry Birds happened in 2009.
Angry Birds Seasons happened in 2010.
Angry Birds Space happened in 2012.
Angry Birds Rio happened in 2011.
all caps, exclamation point, swearing, angry face, no response
This keeps happening.
no..naver
It's an Angry Birds saying.
Flame* to send an angry, critical, or disparaging electronic message.
The English saying "boiling with fury" means that someone is extremely angry or furious. It suggests a high level of anger, similar to a pot of boiling water.
angry rage heated mad