Openly gay actor Brennan, who plays Doug Carter in the teen soap, told the Daily Star that comments online and on the street make him "feel awful".
"I got called 'faggot Doug' on the street a few weeks ago," he revealed. "A lot of gay men have tweeted me to say I have a gay haircut now, which is homophobic.
"Gay men tweet me and say I'm skinny or cry too much, so within the gay community there is self-hatred."
His Hollyoaks alter ego Doug came out as gay in May 2012 after previously having relationships with Jenny (Daisy Turner).
Brennan further admitted that he remains uncomfortable about his own sexuality, adding: "People assume that I am 100% comfortable about being gay but it's the exact opposite.
"The perception is that I should have had all this worked out by the time I got on a show that has put me in the spotlight for being gay. I'm still working it out, I'm very late in my own development.
"To have people message me every day and tell me things, I feel bad because half of me wants to empathise with them and the other half wants to go, 'You don't know what I have to deal with every day'.
"There are so many hurdles I need to get over. It's tricky but it means I need to focus on myself and making me happy."
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