what do I write back?

Key finally replied back to my email, the one letting him know dates I was available for dinner because he asked to get dinner together to catch up. The dates I gave him? February 7, 8, 9. And the date when I sent my email? January 30. Yeah ......

I guess from now on, I will assume his response time is on the order of 3-4 weeks.

I had actually already accepted his flakiness and was prepared to not ever hear from him again, but his email not only reminded me that just when I try to shovel him out of my life, he appears again, but also his actual response really pissed me off. He went on a while about his mom, school, snowboarding, and toward the end wrote this about getting dinner together:

I just re-read your email, and I realized that you had asked about getting dinner. I'm sorry that I didn't write back sooner -- because that deserves a response. Dinner sounds really good, actually, but right now school is really busy because of [some activity]. But maybe we can plan on something right after spring break (mid-March)?

The first part sounds pretty good; at least he's sorry (but must I always forgive him every single time he pushes me to the way-side?). The second part is just absolutely ridiculous. 80% of me wants to write back an angry email and just completely tell him off. The other 20%, the rational 20%, sits back and ponders just what exactly that would accomplish because that may in turn piss him off, and then I really wouldn't ever hear from him again. Part of what I want to do is to let him know just how much he's hurt me, how I feel, but telling him that in the past has never really ever changed things. His response has always been, "But I'm a flaky person, you know that. Don't take it personally."

What kind of a response is that?

So here's why I'm pissed with the second part: who plans dinner with someone, who lives within a couple of miles from each other, a month in advance? Furthermore, I'm more pissed because when I sent my email on the 30th, I had thought about telling him I wasn't free until after my humongous presentation. I didn't do it because I thought it was ridiculous to schedule dinner with a friend 2-3 weeks in advance.

Because I thought it was important for me to catch up with him and get dinner together, I made my sacrifices and gave him dates I was free the week after Jan 30, which essentially was the week right before my presentation-from-hell. I didn't complain; I didn't even tell him I had the presentation coming up. I just nonchalantly told him some dates I was free for dinner.

Now he tells me that he wants to schedule for something after his spring break mid-March? What kind of bullshit is that? Am I over-reacting?

Maybe the issue is that this really is only important for me, and that's why I'm making the sacrifice. But it's not important for him, so he pushes me to after mid-March. So I should just wake up, deal with it, and move on. That seems to be the trend a lot lately: me making sacrifices for others, and nobody caring about me.

So now I don't know how to respond. I know I don't want to sit back and pretend that I'm not upset, but I'm pretty sure I don't want to flat out tell him off either. So it's got to be somewhere in between where I get my point across. But just how upset should I be? I'm not sure. Do I guilt trip him? I want to, but again, what purpose does that accomplish? I'm the one with everything to lose here because I would care more than he would if we no longer talked to each other. And I can't very well blame him for being a flake if I myself take too many days thinking about how to respond that I don't actually respond.

Suggestions welcome.