I'm pretty much just going to echo what Nirguna said, which strikes me as the most accurate: love and compassion are always encouraged, and attachment is always discouraged. However, this is partially tangential to sexuality. After all, sexual inclinations are, at their root, attachments and desires. We don't even need to go into a discussion of why love and sex are different to see why your actions vis a vis sexuality must be judged individually.

What I'm getting at is: Buddhism should never chastise you for your sexuality or your sexual preference, nor will it discriminate against homosexual or bisexual acts. But those acts are forms of attachment, and the love and compassion that is encouraged is all-embracing, non-sexual, and gender-neutral.