I was told i had bacterial vaginosis , is that considered a sexually transmitted disease?

No: It is not an std you can get it even if you are not having sex, acidolphilus or probiotics taken daily can help prevent it, both of those are otc meds.

Usually not: BV is a complex and poorly understood. It's overgrowth of bacteria in the vagina--mostly normal bacteria, just increased amounts. Exact causes are uncertain. BV often behaves like an STD, eg more common after new sex partners and in women with other STDs, and can be passed sexually in lesbian women. But heterosexual transmission is uncertain, and treating male partners doesn't prevent recurrence.