Hi, soulsisterclaire:
From time to time, many Christians still have doubts about their salvation. At one point in time, I did, too. However, this is what Scripture says on the subject:
In Him you also trusted, after you heard the word of truth, the gospel of your salvation; in whom also, having believed, you were sealed with the Holy Spirit of promise, who is the guarantee of our ingeritance until the redemption of the purchased possession, to the praise of His glory. (Eph. 1:13,14)
It is my belief that God has promised us in His Word that we belong to Him forever, that nothing can take us from Him once we're saved.
For I am persuaded that neither death nor life, nor angels nor principalities nor powers, nor things present nor things to come, nor height nor depth, nor any other created thing, shall be able to separate us from the love of God which is in Christ Jesus our Lord.
Rom. 8:38,39
When we backslide, we will feel aloof from God because of sin. And because the flesh is still with us, harnessing sin will always be a struggle. However, if we confess our sins to God, He will forgive us and enter back into fellowship with Him.
J.I. Packer's book, "Knowing God" was a big help in understanding God's attributes and getting to know Him better. When we get to know God more personally, we'll have a better perspective of who we are in Christ. How we apply God's Word to our lives depends primarily upon our spiritual growth. And spiritual growth comes when we study God's Word to know Him better. I hope I'm explaining myself clearly.
Blessings to you,
Pat