I’m exactly the same, I’ve always been worse with my family, yet at work or I’m meeting someone for the first time I manage much better. My theory is that word substitution and creative management to give the illusion of fluency is exhausting so I tend to let it go when I’m with my family, my family wonder how I cope with University and a successful medical career. I think adrenalin also plays a part I know if I’m faced with a medical emergency at work I’m fine! Yet my Mum asking me when I had for lunch today and I struggle to get it out!