If you consider yourself a member of a group or organization, including a church, that is actively homophobic, you are still complicit in their homophobia. The fact that you personally don’t do homophobic stuff is irrelevant. By attending mass and identifying yourself as a member of that group, you are saying that you agree with homophobia, or that you just don’t care about gay people enough that homophobia is a deal breaker for you. When you give them money in the collection basket every week, you are actively choosing to support homophobia financially. That isn’t okay.