The chart-topping singer confirmed earlier this year that he and Maisie were an item after they grew close on the most recent Strictly tour.
Earlier this week, the pair gave their first joint interview, in which they discussed how their relationship first blossomed and the 13-year age gap between them.
However, after this was published, the Wanted star voiced his upset when he saw a comment referring to his romance with Maisie as “controversial”.
“I’ve just read that apparently mine and Maisie’s age gap is ‘controversial’,” he tweeted.
“A woman in her 20s and a man in his 30s.. what the fuck are they implying? I’d love an explanation please.”
Max previously told Hello! magazine that the fact his girlfriend is younger than him “never enters my mind”.
“Maisie has already done so many things that I’m in awe of – I look up to her,” he added.
The EastEnders star agreed: “People ask me: ‘Do you notice [the age gap?’. I never have.
“We’re so like-minded. I’ve got friends in their 30s and 40s. You connect with who you connect with.”
During their series of Strictly – which was the first to occur during the pandemic – Max was the third celebrity to be eliminated, while Maisie made it all the way to the final, finishing as runner up behind eventual winner Bill Bailey.
The 20th series of Strictly is currently airing on BBC One every weekend, with seven couples now left in the competition.