That’s what scares me.
It would be better to die today than chance another step.
You sound terrified and troubled by what you see in your own life.
Everything else in this thread has been true and helpful – I even found myself agreeing with
thistle, which hasn’t happened in ages – but I’d like to answer you from a different direction.
Remember that sometimes God withdraws His grace from you, and asks you to struggle and – yes – even to fall into sin (fighting every step of the way). He does this, in His wisdom, for many reasons, as there are many lessons to be taught by sin and our (losing) struggle against it. You will learn humility. You will learn your own weakness. You will learn contrition, and you will learn repentance. You will learn enough about all these things to realize that you don’t really know anything about them (when before you probably thought you knew much more than you did). You will develop habits of confession and prayer, and you will come to rely evermore on God’s grace revealed in daily life and the Eucharist. All this will make you stronger for the future, and more able to live out the vocation God has set for you when the trumpet blows and you are called to take up arms and take your place on the front lines of the spiritual war we’re fighting.
You must continue to fight temptations, and you must confess your mortal sins rigorously and very regularly, so as to preserve your soul against the fires of Hell… but, at the same time, you must also remember to
thank God for your temptations, and, yes, to thank him even for the times that you failed, for He has brought such goodness and beauty out of your great failings. You must not despair. Your whole life,
even your sins, are a part of God’s plan. Daily, hourly, constantly,
turn towards God and strive to do His will. Trust that He will take care of the rest, and ensure that you do not die in a state in which you would be condemned to Hell.
This may seem to be a bit of a paradox on the face of it – how can Christians hold God in
any way responsible for our own sin, much less
thank Him for it? – but the tradition behind this strain of thought is ancient and pervasive. Not to mention valuable. Sin is still primarily our responsibility, and it is always a terrible thing, but we need not despair over our failure to overcome it on our own. We need to let God work in his own time, and have hope that, if we strive to be faithful to Him, we will not be cast into the outer darkness.
A good Christian spiritual classic which contains some of these themes (and which contains a spirituality that I have found to be
particularly effective against masturbation):
The Sayings of the Desert Fathers, from the 4th Century AD. (Abridged online version
here.)
I hope this theological opinion is not controversial here.