Separation anxiety (aka freakout)

Ahhhh...
Sitting here in absolute silence.
Silence so strong that the clicking of the keys seems loud.
I rarely ever get this kind of silence.
Kids are in bed.
Dave went out on the boat all afternoon.
I'm here with a just opened beer enjoying the silence.
My HUGE bag is packed for the best birthday gift of all, 12 hours of uninterrupted scrapbooking tomorrow.
8am-8pm at my local scrap store.
I signed up the minute I saw the announcement.
It seems rather fitting that my day BEFORE the entire day off seemed to be harder than normal.
Well, we all know that Miles has chosen the most difficult path for almost everything so far in life. Why did it surprise me that it hasn't changed by now.
Yep, we went though a great few weeks.
He was happy! Smiling even! Sleeping too!
That all has reverted back to 'Miles, the grump'.
It's not all that much an issue in MOST circumstances. I love my baby. I understand that he is a bit more difficult than most.
I'm getting to the point...almost...that if I know he is fine, fed, changed, not tired, that I can listen to his cries, sing to him, (sing naughty words TO him ;)
and if he doesn't stop, well...we're OK with that too!
But o.m.g. people!
You know how before you had children, or maybe even NOW for some of you, you would see a baby and instantly think, "I hope MY baby isn't like that baby!" because the baby is crying or yelling or just overall unhappy every time you see him/her?
THAT is MY baby!
He's just an overall UNhappy baby!
People talk to him, smile at him, google at him.
He stares.
He stares and then the big pouty lip comes out.
People think it's cute!
"awww!" they say, thinking it's sweet, you know, that LIP?
Then, the pouty lip turns into squinty eyes and then the roar begins.
Then, he's swatting me in the face, pulling my hair, grabbing my earrings (did I tell you I got my ears pierced a week ago!) and the 'cuteness' is gone and the person who started the whole mess is gone leaving me with the trainwreck.
At my mom's today, it was the worst it's been.
I could not leave his side, or should I say, he could not leave my hip.
I set him down and my mom went down to play with him.
Screaming, crying, yelling, alligator tears.
He was fine when I picked him up.
Imagine his sadness when I had to go run pick up take out. (subway...mmmm...favorite!)
I was gone for 25 minutes. He cried the entire time.
He was fine as soon as I picked him up!
What do I do you guys?
Logan didn't care at all if I left. Kiss on the cheek and happily away I'd skip!
I'm afraid now. Afraid of the wedding we're going to next weekend. The one that is 2 1/2 hrs away. (we're spending the night, JUST dave and I)
Will he cry the whole night?
I'm sad!
Because, as much as it irritates me that the boy can't just be easy ONE day out of his life, I HATE having him cry because he just wants his mama.
Ugh! have any of you gone through this? Because I just don't know what to do.
THEN, we're planning our anniversary trip next month...5 DAYS alone!
We NEEEEEEEEED some alone time SOOOOOO bad, but how can I feel good about leaving him when he obviously needs me.
This boy is so different then his brother was.
I don't know how to be a good mom to such a difficult child!
Do I give in? Carry him all the time? (First, will it be a bad thing for him mentally not being able to play by himself at given times? Although he DOES play in his playpen or on the floor for a good 10 minutes at a time sometimes...SECOND, he's almost 25lbs! He's freaking HEAVY! It's HARD to do that!)

I really need your help and advice.
Please! I'm literally going to go bonkers if I don't figure out this thing here soon!