B, I understand the cycling of emotions and the angry communication, later regretted. To me, there is nothing more painful than the OW, who participated in destroying our families, spending time with our kids. It hasn't happened in my sitch yet, but when H's attorney demanded that my boys spend one overnight a week with H and OW in their new house I went through the roof.
Hurt expressed as anger is hard to live with once we calm down. A couple of months ago I had strong reaction during an email conversation. I caught myself, apologized and admitted that I'm still very hurt and expressed it as anger. I haven't regretted doing that. For all I know H laughed, but it didn't matter. I did it for me. If you can you might try doing the same, not out of fear (OMG, what have I done), but because you wish you would have handled it differently.
Have you and H talked about boundaries during visitation? If not, you need to. Have you talked to an attorney about whether you can request that OW not be around your kids? If you don't have a say in that, decide what's best for the boys and what you can live with and see if H will work with you. If you anticipate OW being with your kids you are less likely to be triggered when she is.
You are hurting, B. There are going to be times when you are triggered. You are still a wonderful, loving person. When you're ready, show who you really are.
