I have a good friend from work - he's older than me but really good fun to be around and very loyal. He's been with his partner (who he met at work) for several years now - they have a serious relationship but chosen not to live together as like their own space. They spend half the week together though.
When he's not with his partner, he regularly calls for chats, sometimes invites me round for a cup of tea after work. It is 100% platonic - we never go out drinking or for dinner, nothing that would verge into date territory.
However when his partner is there, he is paranoid about calling me or receiving calls. It can only be texts. During work hours if I need to call him about something I have to make it clear its work related or he won't answer the call. His tone when he answers these calls is so different too but if I were to call him about work when she wasn't there, he'd be different.
He sometimes calls quickly in what he calls a "window of opportunity". Usually when he's walking to the shops or she's popped out.
This terminology makes me feel very uncomfortable and like I'm the other woman when I'm not. I feel like some shameful secret when all we are is friends. I've alluded to this with him and he skirts around it - I think he's embarrassed.
I really value his friendship but I don't want to get caught in the middle of something if she were ever to find out we talk or I pop round for tea. I don't want that drama but he always has my back and is a really uplifting person to be around.
What would you do?