My husband is a cheat_ cries a Nigerian Woman

My Husband is Always Chatting And Calling Single
Female Colleague

Was at the salon yesterday when i listened to a
lady's complaint. She has confronted him
occasionally and he said nothing is between
them, that she's a very nice lady and would want
to link her up with his unmarried friends (which
he did, but it didn't work out) and she asked him
to be careful.
The first thing the hubby does after taking off his
clothes is to call this lady and ask if she's gotten
home (they drive home together in the lady's car)
and later starts chatting with her till late night
even in her presence. Both office and non-office
related gist.
During weekends he still calls her (she checks his
call log) and chats with her asking how she is
doing, what she's doing etc but nothing sexual
related. But once she found out the hubby sends
her this ''i love you'' smiley (the one with love-
shaped eyes) and confronted him, he said he
didn't know the meaning and would stop. But of
recent he started sending to her again.
My concern is why would a married man keep
such close relationship with a single lady.
She's confused whether to be suspicious of her
hubby cheating with her or flirting and confront
him again but has no real evidence. Is she just
being jealous and insecure. Pls mature advise.
NB: her hubby that doesn't even remember his
own birthday, called this lady and sent her text
very early in the morning.