Will Allah forgive what I have done, and can I stop what I was doing, exchanging kisses with a female relative of mine, knowing that Satan was the third between us, and that we feared Allah and felt guilty?

Friendship between people is divided into two types: friendship for the sake of Allah's obedience, which is desirable and has great virtues, and friendship for the sake of disobeying Allah, which is misery and tribulation in this world and the Hereafter. Allah Almighty says: (Close friends on that Day will be enemies to each other, except for the righteous) [Surat Az-Zukhruf 43:67]. Among the forbidden types of friendship is a man taking a woman as a close friend (khalīlah) without a legal marriage contract. Whoever has fallen into this must repent sincerely and sever the relationship. If she is not married and has repented, and there is no legal impediment, then he should marry her. Otherwise, he should marry someone else, because marriage is the most beneficial means of protecting one's chastity and lowering one's gaze.