You didn't mention your husband's situation, and judging by your guess as to why your mother complains and thinks she needs financial independence, is it because she is now single with a child? Or is it your own family and husband, who is also struggling financially and needs your mother's support to make it work? Whatever the reason, the problem of independence that you are now facing, and not your own, requires the cooperation and support of your husband, and needs to be solved by the two of you together, and that's what family is all about, ah.
If it is already separated and you are alone with your child in school, then the child's living expenses also need to be borne by the father, which is an obligation that he must fulfill, and it has nothing to do with whether or not you can be independent on your own, or whether or not you have the financial ability to do so. So, it's fine for you to say that you need to be independent, but, while doing a good job of taking care of the responsibilities that you need to take on, you also need to fight for the rights that you deserve, and don't add undue pressure on yourself, which will make you more anxious, and let the negative emotions overly affect your life.
When we deal with interpersonal relationships, what we are most afraid of is that the other party has an idea and doesn't say anything, relying on us to guess. But how is it possible to guess what someone else is thinking? Everyone's family of origin, upbringing, and personality are different, so of course they have a different view of things; the same person will have a different view of the same thing at different times and in different emotional states.
We can only rely on our own understanding and knowledge of others to surmise what attitude he may have towards this matter and what he is thinking. So going straight to the question is the easiest and most effective way to communicate. Mom has been sighing and complaining lately, but doesn't directly say what's wrong. Go straight to the point and ask, do you want to go on a trip? Is there something wrong?
Is it that she is unhappy with the old lady in the neighborhood when she dances in the square? Or do you feel that the living expenses we give are too small and not enough to spend? If you know the real reason, then you know what you should do, where to do not appropriate, how to change, in order to get twice the result with half the effort. The process of communication deepens the understanding, better appreciate each other's feelings, and the feelings are deeper.
It's a lot better to have negative emotions affecting your mood than to be on your own right now. Financial independence is really important, for yourself, for your kids, and for your mother. It's not easy to take the first step, find the breakthroughs, start with what you are good at and have experience in, keep building confidence, and believe that the future will be better.