Not sure about much of anything . . .

I don’t really know why I am writing except for the fact that I have contemplated suicide a few times before this moment, but I haven’t really gone through with it.  I suppose I don’t take enough pills or wash them down with the adequate amount of alcohol to get the job done, and, probably, I am scared to do it as well.  I feel that I’d be doing everybody in my family a favor if I weren’t around.  I have a 9 year-old boy whom I love dearly, though, and a 13 year-old step-son who my husband and I recently got full custody of two years ago.  I feel as if he were my own biological child and love him just the same.  I have bipolar illness (I hate calling it a disorder–so I won’t).  I take my meds and see my psychiatrist and psychologist regularly because mental illness runs rampant on both my father’s and mother’s sides.  Each of their brothers committed suicide as well.  To try to make my mental outlook better, my husband and I go to marriage counseling since he had sex with at least 3 other women (that number I know for sure).  He blames that on my mental state and the nasty things I said to him and horrible way I treated him.  By the way, one of the women was my sister.  It is important for you to know that the first time he had sex with another woman during our marriage was 7 months after I had our son which also happened to be 8 months after my mother died of cancer.  I took care of her and held down a full-time job as an English teacher until my son was born and went back to work 8 weeks later.  Then a few years after she “took the voyage,” I had also taken care of my father, who has dementia, for 2 1/2 years until I could physically no longer do it.  I had myself evaluated and hospitalized for having recurring suicidal thoughts, but I never want to go back because hospitals that treat mental illnesses make me want to kill myself even more.  Also, they make you do group therapy, and I hate group therapy along with the fact that they change around your meds because that is only a “quick fix.”  I am only 36 and feel like life has already passed me by, so, my question is: what’s the point of staying?