Husband performance anxiety

I'm ovulating and my husband cannot have sex with me. He's had sex-related anxiety for as long as I've known him but we worked through it early on and have always had an amazing sex life. Now that it actually matters whether or not he ejaculates he's getting these panic attacks and freaking out when we NEED to have sex. I'm being very gentle and supportive but inwardly I am so fucking frustrated and I want to scream. We have 2 toddlers (both conceived without trying) and his work schedule is insane so our sex can't really be spontaneous right now. We both want one more baby but at this rate I don't know how we're going to do it. Just feeling really low. He just left for work after a failed attempt and the pre-seed I used is wasted and leaking out of me.