you can't be serious

So without getting too into my love life, let's just say that when I met my now husband, I was dating his best friend. Yeah, I know that sounds uber-trashy, but it really wasn't, I swear. My ex dumped me way before Hubby and I ever got together, and besides he turned out to be kind of a loser. (My ex-boyfriend, not my husband.) Anyway, to compound that weirdness- my husband's father used to date my ex-boyfriend's mother. (God, we sound really freaky and, like, inbred when I think about it.) This means that both my ex and his mom came to my father-in-law's wake last year. (So, yeah, seeing them there was awkward.) And then today, Hubby gets an email from... my ex. Apparently he just wanted to say "Hi." Am I the only one who finds this odd? I mean, they stopped being friends before Hubby and I even started dating, so they haven't really spoken in seven or eight years, and now my ex emails to say "How's it going?" I don't know. I'm kind of weirded out by this. It's not like I should care if they talk or hang out or whatever; I put up with my husband's ex (Big Sister's mom) on a regular basis, so this should be no big deal. If anything, my husband should be freaked out about spending time with my ex, right? And yet, it doesn't seem to phase him. I suppose I should be grateful that they're both acting all mature and stuff. I mean, I know we're adults here, but honestly, I don't really want to see him. (Again, I'm talking about my ex, not Hubby.) Especially in a hanging out-type of situation. Obviously, if I wanted to hang out with him, I would have made more of an effort to keep dating him. Or I'd have tried to do the whole "staying friends" thing. Or at the very least, I'd have stalked him. And I know I should just tell Hubby that I don't want them being friends, but that seems so high school to me. "You can't be his friend because he dumped me and now I don't want to be his friend and I don't want you to be his friend either. And also, Sally says to tell you that she heard Tommy say that Laura thinks you're cute." Plus, I've always told him that I didn't want to stand in the way of their friendship. (At the time, I thought this was very mature of me; I never actually thought he'd take me up on it.) And Hubby's the kind of guy that if I told him all this, he'd never talk to my ex again. But then I know I'd feel guilty, like, forever. I'm big on holding onto guilt.
So, basically, I'm not sure what to do. It would have been so much easier if he'd never emailed. I guess I'll just wait and see what happens down the line. Let me tell you, though, if Hubby ever has a shindig and invites both my ex and his, there's no way I'm going. I'll just lock myself in my room in my frilly party dress, throw myself on the bed and scream "I'm not coming out and YOU CAN'T MAKE ME." How's that for mature?