I have been in a relationship with my girlfriend for just over four months. We are happy together, and we have had good thoughts about the future. Unfortunately I am confused in one area. Although we have been happily together we have been having sexual desires and our temptations have weakened us. Therefore, we had safe sex with a condom once. Not often but normally it's just other sexual methods.
I need help. Whenever I'm in the moment I don't really think about what I am doing and then whenever I finish whatever I did I have regrets. Even in masturbation I have regrets afterward. I know I am doing sinful things, but I don't know if what I am doing can be forgiven by God. I need some advice.
Just because you have only committed fornication once, it doesn't mean it was "safe" spiritually, or physically for that matter. Using a condom only reduces the odds of getting a girl pregnant or catching a sexually transmitted disease. It does not make the odds zero. For example, the odd of getting a girl pregnant without a condom is 85 out of 100 times. With a condom the odds drop to 20 out of 100 times, which is not close to zero.
While you state that your desires weakened you, this wasn't an unintentional act. You had to have planned it because you made sure you had a condom available. Therefore, there is no innocence involved here.
You placed a limit on your behavior, but that limit was in the wrong place. Your focus was not to put your penis in your girlfriend, but you violated your own goal -- not even by getting carried away, but by planning to do so. The reason it happened is something most people understand and would tell you: the body is designed to have sex. Start the sequence and it will naturally progress to you ejaculating in her vagina. If you understand that you may not have intercourse before marriage, the next question is what about the things done prior to intercourse. Can you do anything so long as your penis doesn't enter her vagina?
Solomon points out the problem when he asked, "Can a man take fire to his bosom, and his clothes not be burned?" (Proverbs 6:27). You can show a hot coal all the affection you want. You can cuddle it and dote on it and it will still burn you. Your kindness to it doesn't change its nature. How often do you hear someone say, "But I love her!" Solomon's point is that your feelings toward your girlfriend won't change the fact that both of you have built-in desires and capabilities for sex. Trigger them and they follow the instincts built into you.
Solomon also asked, "Can one walk on hot coals, and his feet not be seared?" (Proverbs 6:28). Using the same example of a hot coal, if you walk on it, it will burn you. You can apologize and say you didn't mean to step on it, but you'll still be hurt because your intentions doesn't change what it is. Thus, the excuse, "But I didn't mean for it to go this far!" becomes an empty one because your intentions doesn't change your body's drive.
That is why Solomon concludes, "So is he who goes in to his neighbor's wife; whoever touches her shall not be innocent" (Proverbs 6:29). Though he is talking directly about adultery, the same point is true about fornication. When you start stirring up sexual feelings, you are never innocent when thing go further than you wanted.
That is why we are told not to make room for lust and lewdness. "Let us walk properly, as in the day, not in revelry and drunkenness, not in lewdness and lust, not in strife and envy. But put on the Lord Jesus Christ, and make no provision for the flesh, to fulfill its lusts" (Romans 13:13-14). Lust is those thoughts and desires you keep battling about taking things even further. Lewdness is engaging in sexual foreplay that gets the body ready for intercourse. The Christian must recognize the danger and not start a sequence of events that can't be legitimately completed.
If you don't want to reach a destination, you can't start down the path to that destination. "Do not enter the path of the wicked, And do not walk in the way of evil. Avoid it, do not travel on it; Turn away from it and pass on" (Proverbs 4:14-15). No touching each other's private areas. No stroking skin to get you or her sexually aroused. No long passionate kisses that leave you out of your mind. You have to treat each other with respect and not as sexual objects. "Now concerning the things of which you wrote to me: It is good for a man not to touch a woman" (I Corinthians 7:1).
With that comes not talking dirty or showing nude or semi-nude pictures to each other. "But fornication and all uncleanness or covetousness, let it not even be named among you, as is fitting for saints; neither filthiness, nor foolish talking, nor coarse jesting, which are not fitting, but rather giving of thanks. For this you know, that no fornicator, unclean person, nor covetous man, who is an idolater, has any inheritance in the kingdom of Christ and God. Let no one deceive you with empty words, for because of these things the wrath of God comes upon the sons of disobedience. Therefore do not be partakers with them" (Ephesians 5:3-7). You don't stay pure by sexually arousing the other person.
The problem is that you get yourself sexually stirred up and your ability to make sound judgment shuts down. Oh, you will be telling yourself that you shouldn't be doing these things, but it is like being closed off in a glass room. You're banging on the window but your body isn't listening because it is too busy with sexual activity.
Can you be forgiven? All sins that are repented of can be forgiven. But repentance means changing your mind and behavior in regard to sin. You can't keep sinning and expecting to God overlook those sins. "What shall we say then? Shall we continue in sin that grace may abound? Certainly not! How shall we who died to sin live any longer in it?" (Romans 6:1-2).