My question is for how long will his friend be in town?
7 hours is a hell of a drive. My girlfriend used to live 2 hours away and I always hated that drive. For you to visit him every weekend meant you spent 14 hours on the road out of your 48 hour weekend. Wow. That's commitment. At the same time this could be negative for you as well. That much exposure will make him value your time less. This is unfortunate, but it's true. He's seen you so frequently the past couple of months that he doesn't feel like you really needed to spend another weekend together because his friend was visiting. He saw his friend 3 months ago which is why he's now valuing time with his friend more than yours.
You see how this works?
You're a great girlfriend for doing that and he should not have ditched you, but I recommend seeing him a little less to show him that you have a life of your own and he can't just snap his fingers and you drive to him. I wouldn't get too mad about the situation because again, he rarely sees that friend. Just make sure he follows through on those plans the next time.
Cheers
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