People aren’t cartoon villains who are 100% evil 100% of the time, or 100% nice either, people are complex mixtures
they might be charm personified on 364 days but that doesn’t excuse the one day they kill someone
and maybe someone you have down as an asshole from that one time you met them might have been having to deal with their house burning down or their dog died that day and could be normally very lovely
what you do know is:
he avoided being clear about your relationship downgrading it from gf/bf to ‘f’ in introduction to another woman
he left you with people you didn’t know well and ignored you in favour of that other woman for half an hour
you felt unable to speak up to ask what was happening or express your discomfort at the time
you felt unsure if it was his (rude) behaviour or if you were (not at all) over sensitive
when checking out with others who confirmed his behaviour was rude - you felt you had to defend him
So given what you do know then:
I suggest it doesn’t matter if this is a lovely guy having an off day of rudeness
if you are not confident to question off behaviour with him
and are inclined to brush off suggestions that his behaviour was indeed objectively rude
and yet also feel demoralised by his behaviour
then the relationship (or ‘friend’ship according to him) is not good for you
you could be single and grow your confidence to speak up for yourself
and date a man that is more than happy/proud to acknowledge your bf/gf relationship
and reduce your chances of feeling like shit bc of someone else’s rude behaviour
tldr - you don’t have to put up with rude and dismissive behaviour you have many many choices beyond sticking with this guy