That’s very unfortunate. May Allah compensate you and may Allah guide him.
If he keeps abusing you, then keep a distance from him. Yes he is your brother, but he has no right to abuse you in any way. If he doesn’t stop, try to avoid being in his presence as much as you can.
I recommend the following A’mal:
1- Do sujud for several minutes each night and with a deep breath each time say: سبحان ربي الاعلى وبحمده (subhana rabbial a3la wa be7amdeh)
2- Before sleeping, say 100 times لا اله الا الله (la ilaha illa allah) and take a deep breath each time
3- Read this Du’a:
http://www.duas.org/mobile/sahifasajjadia-dua54-removal-of-worries.html
4- Put the Qur’an on your heart and recite verse 82 of Sura al-Israa:
وَنُنَزِّلُ مِنَ الْقُرْآنِ مَا هُوَ شِفَاءٌ وَرَحْمَةٌ لِّلْمُؤْمِنِينَ
5- Read this Dua daily:
https://www.duas.org/Amn.htm
6- Everyday pray 2 rak’as like the morning prayer, then when done gift it to Imam Mahdi. Say O Allah I offer this prayer as a gift to Imam Mahdi. Then talk to Imam Zaman and ask him to help you with this situation. This prayer is very effective
7- After the morning prayer, put your hand on your heart and say 70 times يا فتاح (ya fatta7)
May Allah bless you