This is a very tough and emotionally draining situation Subhan'Allah, may Allah SWT make it easy and deliver you from this. However, as long as you are living there, there is not much you can do about your mother's choices. If you cannot leave then you must occupy your time with beneficial things, things that will take your mind off of the painful emotions, and which will raise your Iman instead. This is the best thing for you, in times of hardship, to turn to the only one who can help you, ALLAH SWT. Make sincere du'aa to Allah, and persist in it, then you will see His mercy rain upon you bi'idhnillah. Give in charity, do all your obligatory deeds plus extra good deeds, do everything that pleases Him SWT, and ask Him to help you and find a way out for you. He SWT will do it Insha'Allah, as Allah SWT says in Surat al-Talaq
“And whosoever fears Allah and keeps his duty to Him, He will make a way for him to get out (from every difficulty). And He will provide him from sources he never could imagine. And whosoever puts his trust in Allah, then He will suffice him. Verily, Allah will accomplish this purpose. Indeed Allah has set a measure for all things.” Surah al-Talaq (65:2-3)
Here are some other du'aa from the Sunnah that you can read Insha'Allah
Invocations for Worry and Grief
Allaahumma 'innee 'a'ooth
u bika minal-hammi walhazani, wal'ajzi walkasali, walbukhli waljubni, wa dhala'id-dayni wa ghalabatir-rijaal .
O Allah , I seek refuge in you from grief and sadness, from weakness and from laziness, from miserliness and from cowardice, from being overcome by debt and overpowered by men (i .e . others) .
Reference: Al-Bukhari 7/158. See also Al-Asqalani, Fathul-Bari 11/173.
Invocations for Anguish
Allaahumma rahmataka 'arjoo falaa takilnee 'ilaa nafsee tarfata 'aynin, wa 'aslih lee sha'nee kullahu, laa'ilaaha 'illaa 'Anta.
O Allah , I hope for Your mercy . Do not leave me to myself even for the blinking of an eye (i.e. a moment) . Correct all of my affairs for me . There is none worthy of worship but You.
Reference: Abu Dawud 4/324, Ahmad 5/42. Al-Albani graded it as good in Sahih Abu Dawud 3/959.
The Dua of Yunus:
The Prophet SAW said in the hadith recorded by At-Tirmithi and others:
The invocation of my brother Dhu-n-Nun, "None has the right to be worshipped except You; glory be to You, far removed are You from any imperfection; I have been among the wrong-doers," none who is experiencing difficulty employs it except that Allah SWT would relieve him of his difficulty.La ila ha illa anta subhanaka inni kuntu minadhalimeen (Ch. Al-Anbiya (21): vs. 87)
May Allah SWT make it easy for you and remove all difficulty for you. You can also try talking to your local imam for help Insha'Allah.
Jazakee Allah Khayran