I live in a town where everyone appears to have it together and I thought that I had to keep up the facade too. I have 2 young kids and can relate far too well to your initial post. The more I've opened up and been honest about what I've lived with all these years, the more I find that a LOT of people around me are hiding very similar lives.
It's hard for me to make a lot of al anon mtgs for the same reasons you list and I've found that this site is invaluable.
I have also found that in the immediate aftermath of a horrible situation (like your H's arrest- mine has been arrested too) my H is all about honesty, apologies, promises etc... And I believe he means it at the time bc he is scared out of his mind. But bear in mind as you talk with him and try to decide where you want to go from here, that in a few weeks, when the fear and recollection of how awful he felt getting arrested has passed, he may and very likely will, go right back to the old behaviors. I could not and did not want to believe this about my stbxah for a looonnnnnng time. It took a lot of pain, a lot of guilt about what I subjected my kids to (they are 6 and 3- two girls) before I accepted it. We are now separated and it's been the best thing for the girls and I.
Thinking of you and sending you lots of support.