(((Hugs)))
My first thought, besides that I'm so sorry you are going through this, is if he asked me how to pay the bills, I'd tell him to figure it out himself. Or google it...or...there's an app or that...>.< my snarky self often intrudes even when I feel like I'm dying.
I applaud you for having the strength to stay in the house with him although if you have anywhere you can go, it's much easier. Assuming you don't, keep your chin up and disengage as much as possible.
It is awful finding out that you were the only one in your relationship...or rather, you thought you were in a relationship built for two but instead turned out to be what? Four? There is just no pleasant way to think about it but now you know what you are actually dealing with.
Get yourself tested, don't forget to eat nutrient dense food (not a bunch of junk), drink water and rest as much as you can. Focus on your kids and actively enjoy hobbies and friends that build you up. Find new things to do. This isn't easy to do but nothing is easy right now. One thing that really helped me was attending meditation classes. We have a local monastery that offers them for free so it's worth looking into although I really struggled at first because my mind wanted to instantly go to dark places.
I also worked really hard on being consciously grateful for literally anything and positive thinking in such a way that required me not dedicating any space to negativity. It wasn't remotely easy nor often successful but I discovered that much of my negative thoughts were just...him. There wasn't much negativity otherwise and little by little, I started breaking through.
Again, I am so sorry and all I can offer are little tidbits of things that helped me and may not apply to you at all other than the health related ones..everyone needs those:)
Your shock will lessen and your tears and pain will settle to a dull roar but that takes time. Anger or even rage will whip you around for awhile but even that will smooth out.
The most important part besides caring for yourself and children is to not allow him back ino your life unless he's remorseful and willing to do that hard work to heal things. You cannot love him into being a changed man. He has o o it himself. There's a lot of excellent information in the Healing Library here in the yellow box to the left at the top of the page.
Please read it if you haven't yet.
(((Hugs)))
Me: 44 BS
Him: 40 FWS
Ow: 47 head case, no obs
5 DD's: 23, 20, 19, 17, 12
Last D-day: August 2012 with lots of very blurry lines.