Will God forgive a woman who allowed a former colleague to see parts of her body online, under the pretext that he was her future fiancé and swore that to her, then he abandoned her?

Islamic law has set boundaries for the relationship between a man and an unrelated woman; it does not approve of a collegial or friendly relationship due to the temptations and corruptions such relationships can lead to. What happened was a transgression of these boundaries and a following of the footsteps of Satan, even though you are still under the protection of your husband, and inciting a wife against her husband is a major sin. Therefore, it is obligatory to cut off the relationship with this man and to offer sincere repentance: by abandoning the sin, regretting it, and resolving not to return to it. Sincere repentance erases what came before it. We advise you to strive to mend your relationship with your husband.