@thetenthofaugust
I would not like this either. And yes of COURSE someone is a 'partner' after being with them for 9 months! Some people on here claim to have been living with their man, and got married in that time!
However, if a man is THIS close to a female friend, I would suggest that he is not as serious about the relationship as the OP is. I also agree that the man in question secretly fancies the female friend in question.
It's also raising red flags (IMO) that the OP has never met this female friend. It's highly suspicious when a man in a relationship/married man, has a close female friend that his partner doesn't know. Why IS that? If you are in a serious relationship/married, why does your partner not know your friends?
Some people on here say everyone should be allowed friends of the opposite sex, and they should be allowed to socialise with them (alone) etc etc, even when in a serious relationship with someone else. But the fact is that NO-ONE will be OK with that long-term.
Indeed, the dynamics of virtually EVERY male/female friendship changes when one of them enters into a serious relationship with someone.
It has to really. If you genuinely love and care for your spouse, you will always put them before anyone else... If a woman is married, she is NOT going to be second to their husband's female friend forevermore. When you're married, your wife comes before any other woman - ALWAYS. If you can't adhere to that you shouldn't be married.