Asshole boss

So my fiance works at this small little shop, so he has a pretty close relationship with his boss. I am bi-polar so sometimes my stupid little thoughts run away with themselves, well now im pregnant so those thoughts also make me cry, well my fiances boss is a bit of an ass. I know the things he says aren't true, but iv got this voice in the back of my head that i call my bipolar friend, well this voice likes to remind me of stupid things and it even likes to create these horrible what-if scenarios, most of the time i can ignore it, but if im having a abnormally emotional day its hard. Well being pregnant those emotional days are more frequent, and of course this boss hired a new cpu technician who is of course female. I have never met her, she seems to only ever be at the shop when im nowhere near it, which means of course all i have is my imagination, i dont really want to hear my fiance describe her so i havent asked. Anyway the wonderful amazing boss decided it would be a good idea to tell me that karen has a crush on my fiance and that they flirt while they work, which may or may not be true because a 90 year old women could walk into the shop and hed try to tell ne shes into my fiance. Anyway tonight i was at my moms house and karen gave my fiance a ride home. And my dad is sick with a tumor in his brain that is progressing his alzheimers, so to say im emotional tonight would be an understatement, and im trying my best not to even bring up the karen thing to my fiance because it really doesnt matter what he says the voice will say i cant trust him, i am sure hed never cheat on me, but on top of all the stress in my life thinking that mayb she is interested in him is killing me. So im sitting here at 1:40 a.m. crying as my fiance snores away, because yknow im crazy and stressed and theres plenty of reasons for me to be crying, but of course the reason isnt any of the horrible things going on, but the fact that karen might try to steal my man.. my brain is horrible, i wish i could shut it down and go to sleep because when i wake up i can go to work and spend the day with my preschoolers and everything in my head will just cease to exist for those few hours, but no my brain wont give me the satisfaction, instead im going to lay here until im so exhausted my eyes wont stay open, and the whole time i lay here the little voice will be telling me that hes going to leave me for karen >.< all because some stupid lil man who likes to joke around way to much doesnt realize when something is funny and when its just going to torture me for the entire time karen happens to be around..