Is my boyfriend accepting hugs from a female coworker a boundary issue?

My boyfriend and I are in a long-distance relationship, and something he said on our call yesterday really, really upset me.
He told me that he had a lot of work at his workplace and was struggling/stressed out. One of his female colleagues asked him if he needed a hug, and he said yes… so they hugged.
I know a hug might sound like a completely innocent thing to some people, but for some reason, it really bothered me. I immediately felt this weird mix of jealousy, anger, and hurt. I honestly don’t even feel like talking to him right now.
He’s been apologizing since yesterday and keeps saying he’s sorry, but I still can’t seem to get over it. Maybe because it’s not really about the hug itself, but the fact that he was comfortable accepting that kind of physical affection from another woman.
So, guys, I genuinely want your opinions:
Am I overreacting? Is this completely normal and innocent behavior between coworkers, or would you also consider it inappropriate if you were in a relationship?
I’m especially curious to hear from guys.. would you think twice before accepting a hug like that from a female coworker if you had a girlfriend, especially in a long-distance relationship?
Please be honest. I’m trying to figure out whether I’m being unreasonable or whether my feelings are actually valid.
Is my boyfriend accepting hugs from a female coworker a boundary issue?
Post Opinion