How can one get rid of the obsessive thoughts about virginity, depression, and unjustified fear after repenting from masturbation, while adhering to acts of worship?

Masturbation is forbidden, and it can be a cause of tribulation. You have done well by abandoning it. The actions you committed that are impermissible are a result of succumbing to whispers (waswas), and the cure for them is to disregard them, increase in the remembrance of Allah and recitation of the Quran, and perhaps consult a trusted psychological specialist.

If the hymen is ruptured, inform your husband that you did not commit zina (fornication/adultery), and that its rupture has many causes other than intercourse, as mentioned by Ibn Uthaymeen. There is no blame upon you in seeking a righteous man for marriage.