Most Helpful Guy
This is a prime example of why you need to face problems head on instead of ignoring them.1
Most Helpful Girl
You are Never going to Continue a Healty Relationship unless You... Confront him here, dear.
However, You may be accused of being a Nosy Rosy, Which is going to be Trouble in Paradise with his own Eyes.
Tell him you have "Heard through the grapevines" dealing with him and some lingo about him and his Ex and some friends of His, And what's up?
If you have no Proof in your own Semi Sweet pudding that he is Fooling around, Then let it go for now until you Know More... Behind his closed Door.
I feel that if she is this "EX," He certainly has no business 'Flirting' with her, Nor Other Girls... You might want to tease him of "Who is in your celly? I will show you Mine any Time."
Good luck. xx0