I feel like I’ve failed as a parent…

My MIL sent me these texts today after keeping my girls while I was at a job thing. She said just me, not her father. I asked her what I did to make her feel that way as I’ve never said anything hurtful like that to her and she said “you’re just always tired” (I’m 4 months pregnant, work third shift, and am going through really bad depression that I hide very well from my children). I explained to her that mommy loves her and even when I’m tired it doesn’t mean I’m tired of her or taking care of her needs. Has anyone gone through this? I know at age 5 they start saying hurtful stuff that they don’t understand but I just can’t get over thinking I made my baby girl feel like I don’t want to take care of her. She’s very well taken care of every day. What can I do? What should I say? She’s the oldest of 3 so this is all a new phase of parenting to me… 💔