What about the sonnets addressed to a man, like Sonnet 20:
"A woman's face with nature's own hand painted,
Hast thou, the master mistress of my passion" etc. etc.
I am not saying that there is no homoeroticism within his works, which your quotation pretty clearly shows. It is a very difficult, convoluted, and, frankly, misleading thing to create a biography of an author through his or her works alone. One of the major reasons for that is because one can never be sure whose voice is speaking. Is this Shakespeare himself or a persona? Many of his sonnets cover themes that often show up in the Latin poets, like Catullus, and the Hellenistic poets as well, where themes of love with both men and women are abound.
Making unqualified biographical claims over an author who left no ostensible autobiography or other records is a very dangerous thing to do because is obfuscates and pollutes scholarship. I would rather say that Shakespeare MAY have been a bisexual because of his use of homoeroticism which seems to be relatively unique in period literature, he may have also been imitating earlier poetic forms made available through recent translations of ancient works, if he didn't read them in the original languages.