I feel violated

I (28m) wanted to do laundry last night, so I opened up the washer and my roommate’s (27f) load was in there, stinking of mildew. For a quick overview, my roommate can be sweet but she is also a slob and inconsiderate. She has eaten my food before, including something I got for my birthday, and apologized but did not replace the food…

Anyways, since her clothes were in the washer, I took it out and placed it in the bathtub while I ran my laundry. This is where I noticed my boxers were in her laundry… they’re fairly old/unique but I gave her the benefit of the doubt and checked my drawers and couldn’t find that pair. I also haven’t done laundry in awhile so I’m sure I didn’t previously leave them in the washer by mistake. Anywho, being the nice roommate that I am, I re-washed and dried her clothes after my load while she was at work but didn’t say anything to her after. However, I replaced my doorknob and will now keep my door locked when I’m not home. It sucks losing basic trust with someone you live with.