The interim boss, who took over in March, believes that the squad made the "club proud" with their performance at Wembley.
"I'm very happy for players because we've been heavily criticised this season and we've got the trophy and have the chance for another one," said the Italian. "It's been a difficult season but the players have made the club proud. It's been hard work but we came through it.
"It's quite a unique situation to be able to win the Cup as a player and then coach the team to win it. I feel honoured to have had this chance.
"We played well, we scored two very good goals, didn't concede too much, they pressed hard in the second half but we defended well and scored two good goals."
Di Matteo has also guided the Blues to the final of the Champions League, which will be played against Bayern Munich in a fortnight.