First let's get one thing clear. When people talk about "sexual fluidity" they may mean that someone who is essentially gay may wind up -- for one reason or another -- in bed with a member of the opposite sex, but anyone who tells you that a person's sexual orientation can change -- that a gay person can magically become genuinely straight [at any age] -- is just dead wrong. Someone as attracted to women as you clearly are will not wake up some day and suddenly [or slowly] become heterosexual.
You also have to remember that sexual orientation isn't just about who you sleep with, but who you really desire on both sexual, romantic, and emotional levels, so your two experiences with men don't really count for much. It very much sounds to me that you want to be with women. Some homosexual people with a very tiny attraction to the opposite sex [as opposed to a whopping big attraction to their own sex] often call themselves bisexual for varying reasons, but in reality they are basically gay. I think this is the case with you.
I'm glad you don't feel full of self-hate, but it's possible that your mother's negative attitude may well have influenced how you see yourself and your sexuality. Based on what you have told me, I would have to say that you are definitely a lesbian, and much closer to a 9 or 10 on the Kinsey scale [if we must talk about the Kinsey scale] than a 5.5. And that's okay! If you feel you are consciously or sub-consciously ashamed of this, you can seek counseling or therapy from a gay or gay-friendly counselor or therapist.
Remember that there is nothing wrong with you and nothing wrong in being gay.