Hello
At her age people to tend to have a lot of experience and have faced ups and downs in life,we rarely see women of her age socializing too often so she has too many things close intact to herself,every situation is handled differently by different people please check sometimes we don't understand but the family unknowingly becomes critical which they feel the family will not understand if they open up.
Please give her immense time to open up don't just come to a conclusion that she has some psychological problem first try to be friendly with her,appreciate her efforts for the smallest things she does,boasting helps.
We can't rule out the effect of hormones please get that checked.uncontrolled and untimely crying can be due to hormonal disbalance.
Next Steps
I appreciate your concern for your mother.its nice to see that you have reached out,please talk to her about her childhood,her friends and relatives and topics she enjoys.encourage her to be more social in her capacity.
Health Tips
if you still see things are not working out you can reach out to professional help,but first try to understand her fully.