Speaking as someone with ED, the more pressure there is to perform, the more likely it isn't going to happen. It's a vicious circle.
My advice is to let it go. It really isn't about you. Don't make orgasm or PIV the sole determiner of whether or not the experience is a good one. Be present and enjoy other aspects of the experience.
Me: 48 - Married, straight, male
Shiela: My wife.
Suzanne: My FWB
Adam: Shiela's LDR