3. He’s mean for no reason.
He doesn’t consider the other party’s feelings or emotions anymore, he just comes across as cold (very cold).
4. He pays no attention/becomes distant
A guy planning to break off with his lady doesn’t pay attention anymore. He actually doesn’t pay any mind to the lady, to what she wants and sometimes he strays/his thoughts stray when having a conversation.
5. He isn’t as close to you anymore
The guy stops intimate conversations, hangs out without you and generally starts ‘doing his own thing’.
If all these signs and more persist, he may have moved on or just not interested anymore.