If I leave my girlfriend, who loves me with a forbidden love, would I be considered among those who are at odds, whose deeds are not raised (to God)?

If the situation is as you described, then you are obligated to abandon this girl and end your companionship with her, in order to safeguard your religion and your character. This is not among the forbidden types of abandonment, as scholars have unanimously agreed on the permissibility of abandoning a Muslim brother if one fears that conversing with him or maintaining ties with him will corrupt their religion, or harm their religion or worldly life. Furthermore, the prohibition of abandonment for more than three days applies to situations of reproach or shortcomings in the rights of companionship, and similar matters. This warning does not include abandonment that is for the sake of Allah.