All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
If your father is as you have stated, that he is insulting the companions like slandering them in relation to their religion and their righteousness, then insulting them takes the person out of the fold of Islam. That is, if one believes that it is permissible to insult them, or insults all the companions, or those whose excellence has been reported in many narrations, like Abu Bakr, 'Umar, and 'Aa'ishah as by insulting them one denies the texts of the Quran which praised them and informed us that Allaah is pleased with them.
Al-Khallaal reported that Imaam Ahmad was asked about a person who insulted Abu Bakr, 'Umar, and 'Aa'ishah and he answered with the following: 'I do not consider him to be a Muslim.'
So if on top of this, your father forbids you from wearing Hijab, and he hates religious people, and you fear that he will prevent you from marrying a suitable and competent man, then this implies that his right to guardianship on you is lost, so you may take your case to one of the Islamic centres to marry you off to a religious person who has good moral conduct.
However, if your father insults some of the companions but not in order to slander them in relation to their religion and their righteousness, then this is dissoluteness, but this does not negate his right to be a guardian over you in marriage; nonetheless, since it is feared that he would an obstacle for you in marriage, then his guardianship over you is lost as stated above.
Finally, the following notes should be mentioned:
1) It is not permissible for a woman to establish an affectionate relationship with a marriageable man. If marriage with this man is not made easy, then you have to end the relationship with him.
2) You are obliged to abide by religious obligations and wear the Hijab as much as you can, whether this marriage takes place or not, even if your father does not want you to wear it as there is no obedience to a creature in matters which involve disobeying The Creator.
3) It is not permissible for a woman to marry herself off without a guardian or his deputy, as the guardian is one of the conditions for the validity of marriage according to the most preponderant opinion of the scholars.
Finally, we ask Allaah to facilitate your affairs and bless you with a righteous husband and help you to get out of this bad environment.
Allaah knows best.