A Situation

Guys help me out here. I need to figure this out.

(Disclaimer: This has nothing to do with me or my personal life, OK. Just helping a friend in need)

There is A
There is B
There is C

A is a girl (oh yes, it's one of these kind of situations..)
B and C are guys.

A used to be with B
Now they are best friends

A met C and now they are best friends too
A thinks that C likes her but is not entirely sure because he drops hints but she doesn't want to be too hopeful
A thinks that she likes C however C doesn't meet her expectations
But A thinks that C is such a nice guy.

B and C might know each other
Because C's best friend used to be B's housemate

A, somewhere deep in her heart still cares for and has feelings for B - although not as strong as before..but it's still there
A is afraid that B will find out about C and not be happy
A doesn't want B to get angry with her
Because B is not on good terms with C's best friend which used to be his housemate

But A wants to let go of B and be happy with C
She is just afraid that the both of them will end up not being happy with her

What to do?

(Again, please bear in mind the disclaimer above. I am just helping a friend in need)