God will forgive anyone who receives His free gift of salvation through faith in Him :)
The moment you trust in Jesus Christ as your Savior, the Bible teaches you are forgiven of all sins (past, present, and future). This is what many theologians call "positional forgiveness." After you trust in Jesus Christ to save you, your salvation is secure no matter what. However, that does not mean you will never sin again. Each time you sin as a believer, you are acting out of your old sinful nature and not the new nature that you received when you were born again through faith in Christ. This puts you out of fellowship with God. In order to be put back into fellowship, the Bible teaches you must simply confess your sins to God and you are immediately forgiven (1 John 1:9). To confess simply means to "agree with God" that you have sinned and trust in His blood to cleanse you. It's important not to confuse positional and fellowship forgiveness, because a lot of people who confuse these terms end up believing salvation can be lost which is absolutely contrary to the Bible. Please understand that all who trust in Christ alone to save them are eternally secure no matter what (John 10:27-30)!
Knowing for sure that you have eternal life is the single most important issue in life. All people are separated from God by a sin barrier that no human effort can overcome (Isa. 64:6; Rom. 3:10, 12, 23). All human beings are born without spiritual life (Eph. 2:1). That is why Jesus Christ, who is eternal God Himself, came in human flesh so that He could suffer and die in our place - as our substitute - on the cross of Calvary. He died on the cross to pay our sin debt in FULL and rose again (1 Cor. 15:3-4). When we believe in Jesus Christ for our eternal life He has promised to give it to us:
"Most assuredly, I say to you, he who believes in Me has everlasting life" (John 6:47).
"Most assuredly, I say to you, he who hears My word and believes in Him who sent Me has everlasting life, and shall not come into judgment, but has passed from death into life" (John 5:24).
To "believe" is simply to be convinced that it is true (Rom. 4:21) that you cannot in any way contribute to your own salvation and instead you trust Jesus alone to give you that life freely - a gift of unconditional eternal life. It means to believe His promise to give eternal life to all who believe in Him for that life. It really is that simple!
The Gospel of John is the only book written for the sole purpose of showing people how they can have eternal life (see John 20:30-31) and it mentions the word "believe" as the sole condition 98 times!
This link helped me when I was struggling with my salvation:
http://faithalone.org/tracts/ycbs.html
Also, see the book "How to Forgive Ourselves Totally" by RT Kendall. I believe this will help you tremendously. You can also watch him preach the sermon here:
https://www.youtube.com/watch?v=abnkWjho2Ds