Why would he rather be alone than be with me?

During the week why don't you see each other? An hour away ain't trivial, but a LOT of people handle DAILY commutes farther than that, while maintaining marriages and families, so if you two are so committed, you might be able to handle a bigger effort.

UNLESS of course, he (and/or you) are too busy. But that means he's not getting a bunch of down time, right? So if he's actually really busy during the week, then he's NOT getting his personal time, is he? Which means Friday or the weekend might be his primary chance to be by himself.

See, the fact that you guys can't make a two hour round trip for each other during the week points to either A) you two are legitimately super busy, so cut him slack on the weekend or B) you two aren't that committed so don't expect all his free weekend time. Either way, he might deserve a break from you.

Or of course, the third option is he's lying and wants to do something else entirely and keep it from you. Is that your worry?

But there are a ton of guys who do think more time by themselves would be terrific, even if you're a wonderful girlfriend. Don't assume you're SO entertaining that he must crave as much time with you as you want from him. Rather, some guys like to be alone sometimes (and some insecure girls can't handle it. And freak and pressure and make it worse, and guess what he starts wanting more of: time away from you! ) Just don't be that girl.

If you are really in a "serious" and "committed" relationship, you shouldn't at all be asking this question in this site. But asking him. In any deep relationship absolute transparency and communication is vital. You should ask him this yourself and deal this concern with him in total honesty, hold nothing back nor secret. It seems that you lack some trust in him, build your trust, don't spy on him or think badly about him, but trust him. If you take offense, tell him about it, but in a loving way, he should try and understand.

Honestly it just seems like he still needs time to find out if he is still going out with the people from work and needs to get back to you. Arrangements can change on the spot sometimes and be made up again. He just wants to check his schedule. Sometimes guys keep the best for last on their schedules, looking forward to spending time with a loved one (or having sex ;) ) is sometimes better than doing it immediately, and still have unfinished business or things to worry about.

You should watch out for him and see if this starts happening more and more often. If it does, ask what's going on. If this only happens once, then leave it be. Something might have happened and he really doesn't want to talk about it with anybody.

I think there is something going on with him because when he hasn't seen you all week, he'd rather be alone. Watch out for him. See if he does it next week and if he does, have a serious talk with him.