A few thoughts.
1) Don't look to your mother for support. She doesn't know how to give it.
2) Her generation, and previous ones, consider psychiatry and psychology (they don't distinguish - they're the same, in their eyes) to be 'quack' medicine. And that's because it used to be, many years ago. It's far more precise, far more balanced and scientific these days. So any hint from them that you need to see someone in that field - check it out but chances are, it's a stinging criticism. And if YOU mention you need to see someone like that, or your child does - you are the worst parent of all for giving in and believing a quack. Get on with being a parent and stop trying to cop out, will be the comment.
3) in my opinion, if you DO take medications which help you feel in control, and you DO end up telling her how you feel - about flamin' time. Don't let that stop you getting medications if you need them. I suspect she needs to be told, now and then, especially if she thinks her mere chronological age gives her every right to walk rough-shod over your feelings and your needs.
4) Learn to handle her comments with humour and sarcasm. She's responding to your plaintive cries with, "Wake up, grow up, face your responsibilities," answers. "Don't bother me with your problems, you brought them on yourself. There's nothing wrong anyway, it's your imagination."
A suggestion - next time she says, "Well you're the one who wanted kids," reply with, "Do you know who I could go to, to get them shoved back in?" Look incredulous, delighted at her suggestion. make a big thing about being able to turn the clock back. You could even comment, "Hey! What if I get them all frozen, put in suspended animation? Then by the time they're defrosted, they'll be someone else's problem. Better still - I'll get myself frozen and tell them to thaw me out when I'm sixty. because at sixty, I'll know everything and be free to do and say what I please."
If you use humour in this way, and she gets offended, you can always reply with, "Couldn't you tell I was only joking?" I actually really hate it when people do that - use "I was only joking" as an excuse for being rude or mean, but sometimes, in a situation where you need to turn the tables, it's briefly justified.
To summarise - stop trying to lean on her for support. She is useless at it, refuses to support you and is only making you feel worse. There are better ways to get support (like here). And have faith in yourself. She is dragging you down, but if she is so perfect, she must have got something right - you. You don't need her sympathy or support. Give it to yourself. And look deep inside yourself - why do you go to her, knowing what she will do to you? Are you still the little girl trying to get her to notice you and to show that she cares? If so, find another way. This is dragging you down. And there are other ways. Healthier ones.
(I suspect somewhere in there, she delights in opportunities to show you how much more capable she is than you - she is competing with you at some level. And to win, she has to drag you down. This isn't conscious, it's just the way she is made. So stop competing back. Go elsewhere for support. When you have coffee with her, talk about the weather. Her corns. Ask her about her health. Do not mention your own or the kids'. It could well annoy her to the point where she will begin to interrogate you about how the kids are doing. Don't give her the answers she's looking for. Tell her everything's fine now. And prime anybody else in the family to also keep their traps shut around her.)
Good luck.
Marg