if you passed out during your attempt in November, your brain could have suffered from being deprived of oxygen. Brain damage would ensue under such a condition, though not major. If you are currently on some other form of medication, that too could cause memory impairment. Finally, your emotional state could also be causing your memory issues. Emotions like anxiety, depression, or confusion could easily cause these issues.
You should talk to someone - your doctor, your parents, a friend, about this. Lastly, know that many people care about you, but the fact of the matter is that no-one can care about you more than you care about yourself. If you are suicidal, something (or many things) need to change in your life - the only person who will ever be able to make those changes is you. This is not a dress rehearsal - you get one slice of time to experience all there is to experience, and then you are done. Life will sometimes be harder than you think you can take, and sometimes more beautiful than you can imagine - and more often than not, it's the harder parts wherein the most beauty lies.
DO NOT BE AFRAID TO MAKE YOUR LIFE THE LIFE YOU WANT IT TO BE!
No one else will do it for you, but lots of people will try to hold you back - wish them well, and utterly ignore them!!