Jonathan Majors is facing an explosive new lawsuit filed by his ex-girlfriend Grace Jabbarimonths after he was found guilty of misdemeanor assault in the third degree, as well as recklessly causing physical injury and harassment in the second degree. RadarOnline.com has learned that Jabbari alleged two more undisclosed instances of physical abuse prior to his arrest within her filing seeking retribution for battery, assault, intentional infliction of emotional distress, malicious prosecution and defamation. According to the bombshell docs obtained by RadarOnline.com, the ex-Marvel star has mad…