I have enough heroine to successfully overdose and end my life. I'm just waiting for the right moment to put the needle in my vein.
That sounds like it is a horrible feeling that you're dealing with right now and I think that you should reconsider, but I must ask why do you have to wait until later?
I'm too afraid of the possible complications.
While I understand you must be going through something horrible, it is good that you're stopping to think about the complications. A lot of people will miss you if you kill yourself, such as family and friends.
Like I care about what other people think of me.
You may not care about what they think of you, but imagine how they will feel? You should seek out some sort of psychiatric care for this, and I am willing to go with you so that it will be easier. You can make it through this!