My Wife's best friend is a man. He was my ex-colleague and my
wife's best friends since secondary school. He's not married. While
me and my wife have 2 kids.
As best friends, they see each other and hang out together a
lot, like everyday.He sends her to work and sends her home from
work everyday as their offices are in the same building. So they
also have lunch and dinner together every weekday. They also go out
during weekends to pubs and cafes. This has been like this for many
years, even before we got married.
She said that they are just best friends and their relationship
is platonic and they are not lovers. But many times i have
questions and some doubt..
Is it possible for a married woman to have a male best friend
like that.
Your statement is a value statement;
technically you are asking if it is possible for women to have
platonic male friends - adding a 'married' presume that somehow you
do not feel 'right' for married woman to have close guy friend/s.
Unless you have unearthed some critical information to suspect that
they are potentially having an affair, if not, it's likely to be
issues relating to self-esteem and/or trust rather than issues of
infidelity.
As much as you are thinking if
their relationship is 'more than meets the eye', honestly: if they
are sharing such close relationship since secondary school days,
then why did she choose you instead? (unless you are saying that
you knew her earlier).
I am not in the school of 'preventing anticipated infidelity',
which usually bring about an overall negative output; learn to work
towards developing the relationship in such a way that it has a
natural mechanism to ward off infidelity. For example, if her best
friend is having lunch and dinner everyday, my question would be
then why are you not at least having dinner with her?
Perhaps you might have some concrete, practical reason why this
cannot be done, but at the end of the day, it is still a choice
made - regardless of reasoning.
I do not view it as a warning
alarm since this is a routine that has already been established way
before you are married to her, so I would see it as manageable
risk. However, I would think that it is a good time to reflect on
the state of your relationship: if you are not putting conscious
effort to spend quality time together (not just as a family, but
also to look into having couple time), then this might be something
you could think and work something out reasonably.

Cheers