Vinicius was sent off for pulling an opponent's hair during Real Madrid's win over Villarreal last weekend and received a four-match suspension. The punishment rules him out of the Clasico against Barcelona on October 25.
The 26-year-old has also been subjected to repeated racist abuse from opposition supporters since joining Madrid in 2018.
"He's a spectacular kid who it's easy to have a good relationship with. He's a fantastic boy," Mourinho told reporters.
"Tremendous credit to him for the fact that he keeps living and surviving and still having a smile.
"If it were me in his place, probably I wouldn't be here. In this last summer I would have forced an exit to a league, a country, to somewhere there are rival clubs and stadiums that respect him."
Despite those experiences, Vinicius committed his future to Madrid by signing a new contract that runs until 2032.
Mourinho believes the winger's love for the club and the city has convinced him to stay, despite the challenges he continues to face.
"Because he loves Real Madrid, for loving the club and the city, for believing that things can always improve, he renewed and he keeps on smiling," Mourinho said.
"He's human, so people can influence him negatively, but no one can take away his joy of living and working and being with his team-mates."
The Madrid coach also expressed relief that Vinicius received a four-match ban, suggesting the disciplinary authorities could have imposed an even harsher punishment.
Mourinho substituted the Brazilian during Wednesday's 4-3 Champions League victory over Roma, as the winger continues to search for the form that helped him win the competition twice under Carlo Ancelotti.
Questions also remain over how Madrid can get the best out of Vinicius, Kylian Mbappe and Jude Bellingham in the same team without compromising their balance.
Madrid now face Sevilla on Sunday as they look to keep pace with La Liga leaders Barcelona. Hansi Flick's side have won every match this season and hold a six-point advantage over fourth-placed Madrid.
The controversy surrounding Vinicius comes amid growing tension between Real Madrid and Spanish football authorities over refereeing decisions.
Madrid have criticised officials following several results this season, including their 2-1 derby defeat against Atletico Madrid in September.
The club also called for La Liga president Javier Tebas to resign on Friday after he compared Madrid's efforts to discredit referees with propaganda techniques associated with Nazi official Joseph Goebbels.
Tebas later clarified that his comments referred to propaganda methods rather than Nazi ideology.
Mourinho declined to become directly involved in the dispute but made clear his frustration with the situation.
"I don't want to talk about this, there are limits and there are limits. You can only excuse it if it's a clinical case – otherwise there's no excuse," he said.
"I don't want to go down that road. Madrid and its fans understand what they are up against.
"For the prestige that the league has abroad, for being the current world champions, it's better if we try to keep this here and not let it get out to the world."
Real Madrid have called for the resignation of La Liga president Javier Tebas after he compared the club's communications strategy to the propaganda techniques of Nazi official Joseph Goebbels.
Barcelona have received a major boost ahead of Saturday's La Liga clash against Real Betis, with Hansi Flick confirming that Raphinha and Frenkie de Jong are available again after injury.
Barcelona have received a boost ahead of their La Liga trip to Real Betis, with Raphinha returning to group training after suffering a knock while on international duty.
Real Madrid believe Endrick has taken an important step in his development after the Brazilian forward delivered an impressive performance in a dramatic 4-3 Champions League victory over Roma.
