I have known a couple of transsexuals. I was quite happy to be friendly with them. One, however, did like to talk about their operations and complications an awful lot -- not interesting, thanks. The other one was a much older person who'd only had the sex change in their 40s or something.
My own view is that a male who has a "sex change" does not become a female. He becomes a non-male, perhaps with a female persona. There is more to being a woman than not having a penis or testicles or facial hair, and having breasts. But, hey, whatever. I'd be as happy being their friend as any other person, providing we got along and had anything in common. Why not?