You do not mean to blame Him, or accuse Him of injustice, for you feel that His indifference and rejection of you are fully deserved because of your unworthiness. And this very subterfuge leaves you at liberty to indulge in your doubts under the guise of a just and true appreciation of your own shortcomings. He only loves and cares for the lambs that never wander. He only cares for and visits well people. From the beginning to the end of your Christian life it is always sinful to indulge in doubts.
Doubts are all from the devil, and are always untrue.
And the only way to meet them is by a direct and emphatic denial. And this brings me to the practical part of the whole subject, as to how to get deliverance from this fatal habit. My answer would be that the deliverance from this can be by no other means than the deliverance from any other sin. It is to be found in the Lord and in Him only. You must hand your doubting over to Him, as you have learned to hand your other temptations.