So we had a tiny discussion, oh about 1 minute on cooking and I always cook for my mom, and deliver it to her too, and I said, "Hey I cook good Mom, huh?" and to that she replied, "Well not really, not all the time", and when I was making dinner tonight, a quickie because I'm freakin' tired, she scoffed at it and said, "that will do". I'm pretty freakin' mad right now, so of course I remained very nice and walked away with a cute joke, and now I'm seething by myself in my office and want to know what others think before I say something not so nice!
Walking away with a joke doesn't give her a sense of the consequences of her words, but it still may be the best reaction AFTER you have told her at least once that it hurts you. Laughing is best if it can be genuine. You might as well laugh, because taking everything she says seriously is just too sad.
Does she have dementia? One of the characteristics is reduced inhibitions. To a certain extent this happens as we age but it is exaggerated in dementia. They say what they think, without running it through any filters first. If the roles were reversed, you'd probably say "Yup, Mom, you cook good!" even though hardly anybody cooks well every single meal. But it sounds like Mom just blurted out the first thing that came to mind, without consideration of your feelings. She may not have as much control over that as she would wish.
I hope you get to spend some time with people who are nice to you, and who have normal social filters in place. It is worth talking to your mom about how her comments make you feel, but she may be past a point where you can count on her for positive reinforcement.
Also consider that she is just plain unhappy. She doesn't appreciate much about her own life. If I were that unhappy, I might not feel like saying thank you no matter how hard the other person was trying. In other words, try not to take it personally.
For your own sanity, try to stop expecting her to be grateful. Maybe try to get her to contradict her. You say that the food isn't very good tonight. She will reply, "It's not that bad." At least it will be a change. You could keep a chart of the negative things she says, and joke with her about it. It might remove the sting of rejection you feel.
My daughter and I lovingly mock my husband because his most enthusiastic praise is, "It's all right." Having her on my side is a great support. Without it, DH would have a cluster of lumps on his head from my frying pan!
I know, growing up, I did not appreciate my grandmas cooking every day.....I just knew better than to mention that to her.
I just suggest you take a deep breath before you deliver the next meal and like Jeannie mentioned look for your validation from people more able to supply it.
Best Regards,
L