Complex sentence: Barry spent a long time after this feeling sorry for himself and became a bit of a Janine (sensing an opportunity to manipulate some money out of her boss) started worming her way into Barry's affections.
Split into simpler sentences: Barry spent a long time after this feeling sorry for himself and became a bit of a recluse. It was around this time that Barry's employee Janine (sensing an opportunity to manipulate some money out of her boss) started worming her way into Barry's affections.