Would you say there is trouble in paradise or something?

So a guy I know has recently been cheating on his girlfriend he was kissing another girl at a party and not speaking nicely about his girlfriend. I noticed on his Instagram he hasn’t posted her in over a year. I know what his doing is pretty disgusting I don’t agree with the behaviour, but it’s not my place to say anything really.
Would you say there is trouble in paradise or something?
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