Hello,
Sorry to hear you are feeling down, It doesn't really matter if it's you or hormones, cause either way its YOU and its happening.

End of the day blues can be triggered by being over tired, try having a sleep in the afternoon and see if your emotions and night time stress settle down a little.

Being with inlaws or anyone else 24/7 is enough to stress non pregnant people, try and find time to relax and be on your own. Sometimes it's easier to say you have a headache or migraine and need to lay down just so you can have 15 mins of time out rather than asking for space.

I remember I pretended I had diarrhea for a week just so I could spend lot's of time in the bathroom to get away from my mother in law ...lol