Stop second guessing yourself.
Don't call him.
You're just in a "low"...that's when you miss the SOB.
Keep looking up at the top of the hole.
See that light?
Go towards it.
You'll have your grip back in no time.

Don't you see the pattern here?
You feel good for a while, then you crash....feeling good one day...down the next...
I promise you a day is coming when the highs will last longer and longer and the lows just won't be quite so low.

That is the process. We all go through it.
It IS possible to maintain some dignity in this process though.
YOU JUST DON'T CONTACT HIM.

Let's see if this helps...

He betrayed you.
He betrayed his daughters.
He lied to you...right to your face.
REPEATEDLY.
He's making future plans with Cassie...a grade A piece of crap pitifully sorry excuse for a woman.
He doesn't help to even buy diapers or formula or food...he was not even calling to see if you and the kids needed anything.
He left you.
Left the babies.
For a slut that will screw him over the minute another man looks at her twice.
He's dead to you.

Should I go on?
I can....