It's hard to see your partner go downhill. Put yourself in her shoes, op. Say you are married over 20 years and have kids together. Now that spouse can't do anything for you. Care taking is alot of work. Shes just going to complain which is reasonable. Just listen or try to talk to her about accepting old age. Teach mom how to do somethings on her own. Be the one to call her cause that gives you a bit of preparation in hearing all the stressful things. Think about finding someone to help her in household chores if needed.

Thank you for sharing your concerns with us. I’m truly sorry for what you’re going through regards to your father’s illness and your mother’s relationship. It is understandable the way you feel for this whole situation that overwhelm you. Even in the darkest moments in our lives there’s always hope. In regards to your mother venting it would be wise not to suggest using words but to be willing to listen and only use words when it is necessary. I encourage you to listen and let her ventilate all her stuff and when she asks you questions or your opinion then you can speak. I hope this helps. . Sending you hugs. I will keep you in my prayers, my friend. Keep us posted, Ok? Sending you hugs. I will keep you in my prayers, my friend. Keep us posted, Ok?

OP, I am a Hospice Chaplain. 90% (at least) of my job is to listen and to just be present. I use a lot of active listening. Phrases like "That must feel so scary", "I'm really sorry you are hurting", "How can I help", ... are often the most helpful. You don't always need to fix things. You can just be present to hold space for your mom. If you don't know what it means to "hold space" for someone, this article explains it well. https://upliftconnect.com/hold-space/

Remember, it's really important that you take care of yourself as well. Eat healthy, drink water, sleep, and spend time outside every day. Wishing you and your mom peace.

You have to work to set aside your judgments and just be fully present. When she’s talking, stop your mind from wandering off to solutions. Just listen and then do your best to paraphrase. With the example you gave, I might respond with, “It sounds like you’re really frustrated with dad not being able to follow through on tasks he’s promised to complete. That’s sounds really stressful.” If you’ve paraphrased it correctly, she’ll sign-off with an agreement. And if you got it wrong, it’s not a big deal. She’ll clarify. And if she wants you to help her solve it, she will ask. Trust that.

One of our most basic needs as a social creatures is to be acknowledged. We want to someone someone sees us and hears what we have to say. Readjust your purpose in speaking with your mom. Switch your role from problem solver to listener. Let go off any responsibility to fix her or her situation. It’s really hard to do. Maybe have a sticky note nearby when you speak with her with a reminder: “Paraphrase, not problem solve.” Or something that works for you.
Hang in there.

First, acknowledge what she is or must be feeling:

“It must be really different and may feel scary that dad can’t do things around the house anymore. That’s really tough.”

THEN offer to paint.

The problem isn’t the paint, so don’t jump to that.

"That sounds really hard" "I'm sorry that you are dealing with all this." "It must be hard to see dad struggle." "I know how hard you're working to take care of dad and the house, I really appreciate you." "I know it can be hard to take time for yourself when you are caring for someone else." "I'm thinking of you." It okay to just keep saying those things as appropriate-it sounds like she just wants to been seen.

Listen. But set your watch. Listen for 10-15min, whatever you decide. You can do that. Then, "you have to go". You owe her understanding. No one owes anyone a monopoly on their time.

Just make understanding noises or say “that sounds tough”. Or “ I hear you”

She is scared and exhausted and needs to vent. You cannot fix this. She does not expect you to.

Is she getting enough sleep? That could have a big effect on her mood too.

She wants you to validate her feelings. "That's so upsetting that dad can't do the things he used to be able to do." Or "I'm sad about dad too and scared for the future." Don't try to fix things or give advice.