Or in the situation orchestrated by your mother, 'one woman's sorrow is another woman's joy'...
I really appreciate your courage in writing about this situation... most women keep silent, and so little is known about what is happening behind closed doors. I'm amazed your mother found a lover and was not scared about being discovered or even, betrayed by him...
At the very least, she should be trying to help her daughter get out of the situation she placed her in so very irresponsibly, ie without making much effort to understand who she was marrying her daughter to... I hope she makes it out with her children... at least she has you to confide in, which must be a comfort.