Taking a break in a relationship?

My boyfriend and I have been together for 3 1/2 years. There's been times in there when we haven't been together officially but we've always stayed close. My bf used to hang out with REALLY stupid people and he's slowly drifting from them ( thank god ) but the other night when we were supposed to hang out he basically ditched me to chill with them. The next day he was having problems with his phone so I was checking it out and a text popped up from some chick. Long story short I found out him & his friends had been hanging out with this girl and my bf made a comment towards her & told her she was hot. He said he did it to be funny in front of his friends ( it actually was in the context of a joke ) and even though it was a joke it still upset me & we've been arguing all week so we're taking a break. We're not seeing other people or breaking up basically we're not talking to or seeing each other. Is it healthy to take some time away from each other and have this space in a relationship, ESP. A long term one like ours?