My FMIL Vent!!

Ok girls so FH and I bought a house last January. We did a lot of work and finally moved in last April. Through out the whole process (and through out wedding planning) FMIL and FFIL have been very supportive and helpful. They really want nothing but the best for us. Needless to say I've been very stressed out lately with everyday life and wedding planning.
FH and I come home last night and there is stuff all over our house. She went to the store to buy us paper towels and water and stuff, lets herself in when we are not home and leaves stuff everywhere. This isn't the first time she has done this either. Last time was just last Saturday at 11 pm when I was in bed and FH was out with his friends and I got up from bed thinking someone was in the house but she just dropped things on the table and left. On Sunday, we were all at a christening on FH's side of the family, and I told one of his nieces that he doesn't see often that they have to come over one day to see the house and she responded to me 'Oh grandma took me there a while ago when you and Uncle Rob were at work'.
SERIOUSLY ***!!!! I know she means well, but I'm getting a little frustrated. I feel horrible for asking her not to let herself in when we are not home because she thinks she is doing nothing but good, but it's just weird to me. My parents would never even stop over without giving us a heads up. it really makes me feel uncomfortable in my own home bc I can never just relax bc who knows when she is stopping by.
Sorry for the long vent...but what do I say to FH and his mom?

I would start with FH. Tell him you are weirded out when she just lets herself in. Plus she is taking the fun out of you getting to show YOUR house off.

If all else fails tell he what happens if we want to do it in the kitchen and she walks in.

Or tell her you want the key back and to please refrain from coming over without calling.

You're good I would have said something after you thought someone was breaking in

Why does she have a key to your place to begin with? I would start there ... Make it magically disappear from her key ring! Next, set up bear traps along the perimeter of the house to prevent her going in your house through a window ...

All joking aside, it's great that she wants to help out ... but letting herself into your home unannounced is just not right. What if you guys thought your home was being broken into, and you grabbed a weapon of some sort? That could have been ugly! My mother knocks on the door and waits for me to let her in, even when I know she's coming over, and I would expect the same respect from my FML(yes, I left the 'i' out purposely). You should definitely talk to FH and see if there is a way she can give you a heads up so you know to expect her - and if she's dropping things off, put everything neatly on the table for you so you don't come home to a mess. I'm sure she would want the same courtesy, so she really shouldn't get offended! Best of luck to you!

My FMIL and FFIL both have keys to our house, but that is just in case of emergency. They would never enter my home without me knowing. They would never buy us household goods too.
Talk to your FH and let him know you are comfortable with anyone coming in the house when you are sleeping or when neither of you are home.
What if you two were naked running around the house together? Hey maybe that would stop her?
Good luck!

omg that is crazy! she should not be coming to your house unannounced
Have FH talk to her and say how much you appreciate what she does for you, it would be nice if she could just call or text before she comes over from now on.
either that or install an alarm system and dont give her the code...she will learn her lesson real fast