When we walk through the valleys in our mind our tendencies in our human frailty is to look down. The longer we look down the more myopic we become. We become focused on our past/present failures and then they become magnified in our mind.
As a new creation in Christ you do not have the authority to crucify yourself. Your sanctification is a process, you are not going to be perfect in anyway shape or form. If you could, what is the need of Christ? I know it is a rhetorical question but I just wanted to make the point.
I have found that when these attacks from within and without occur that praise for what God has done is one of the most effective defenses. It is not my perception that matters, it is God's. It is from God that my identity originates. You are one of the sons of God.
1 There is therefore now no condemnation to those who are in Christ Jesus, who do not walk according to the flesh, but according to the Spirit. 2 For the law of the Spirit of life in Christ Jesus has made me free from the law of sin and death. 3 For what the law could not do in that it was weak through the flesh, God did by sending His own Son in the likeness of sinful flesh, on account of sin: He condemned sin in the flesh, 4 that the righteous requirement of the law might be fulfilled in us who do not walk according to the flesh but according to the Spirit. 5 For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit, the things of the Spirit. 6 For to be carnally minded is death, but to be spiritually minded is life and peace. 7 Because the carnal mind is enmity against God; for it is not subject to the law of God, nor indeed can be. 8 So then, those who are in the flesh cannot please God. 9 But you are not in the flesh but in the Spirit, if indeed the Spirit of God dwells in you. Now if anyone does not have the Spirit of Christ, he is not His. 10 And if Christ is in you, the body is dead because of sin, but the Spirit is life because of righteousness. 11 But if the Spirit of Him who raised Jesus from the dead dwells in you, He who raised Christ from the dead will also give life to your mortal bodies through His Spirit who dwells in you. 12 Therefore, brethren, we are debtors--not to the flesh, to live according to the flesh. 13 For if you live according to the flesh you will die; but if by the Spirit you put to death the deeds of the body, you will live. 14 For as many as are led by the Spirit of God, these are sons of God. 15 For you did not receive the spirit of bondage again to fear, but you received the Spirit of adoption by whom we cry out, "Abba, Father." 16 The Spirit Himself bears witness with our spirit that we are children of God, 17 and if children, then heirs--heirs of God and joint heirs with Christ, if indeed we suffer with Him, that we may also be glorified together. 18 For I consider that the sufferings of this present time are not worthy to be compared with the glory which shall be revealed in us. 19 For the earnest expectation of the creation eagerly waits for the revealing of the sons of God.
I really want you to concentrate on the sons of God part of this epistle.
Soli Deo gloria,