It is not permissible to pray against oneself asking that one be cursed, even if it is conditional

It is not permissible for the Muslim to pray against himself, asking that he be cursed or otherwise, even if his intention is to prevent himself from doing something or to encourage himself to do something.

That is because the Prophet (blessings and peace of Allah be upon him) said: “Do not pray against yourselves except for good things.” Narrated by Muslim (920). And he (blessings and peace of Allah be upon him) said: “Do not pray against yourselves, do not pray against your children, and do not pray against your wealth, lest that coincide with an hour when Allah is asked and He answers your prayers.” Narrated by Muslim (3009). This is what the scholars have quoted in the commentary on the verse in which Allah, may He be exalted, says (interpretation of the meaning): {And if Allah was to hasten for the people the evil [they invoke] as He hastens for them the good, their term would have been ended for them} [Yoonus 10:11].

Qatadah (may Allah have mercy on him) said: This refers to a man praying against himself and his wealth for something to happen for which he would not like the prayer to be answered."(Jami‘ al-Bayan 15/35).

Dr. ‘Abd ar-Razzaq al-Badr (may Allah preserve him) said:

One of the important matters to which the Muslim must pay attention in his supplication is that he should understand what he is asking of his Lord, may He be glorified and exalted, and he should not be hasty in what he asks for. Rather he should reflect properly on his situation, so that he will be able to decide what is really best and most appropriate to ask for, and what is bad and worth seeking refuge from. That is because many people, when they get angry and impatient and things happen that upset them, may pray against themselves or their children or their wealth, saying things that they would not be happy with if they came to pass. This stems from undue haste without thinking of the consequences."(Fiqh al-Ad‘iyah wa’l-Adhkar  2/255).

So what you must do is repent and seek forgiveness, and regret offering such a supplication. You should also be keen to make yourself humble towards your husband and obey him in that which is right and proper, without arguing or fighting. You should offer a lot of supplication for him, asking that he be blessed and guided, and you will find the reward for that with Allah, may He be glorified and exalted. We ask Allah, may He be exalted, to accept your repentance and forgive you.

We have previously explained in the answer to question no. 6262 that expiation for breaking an oath (kaffarat yamin) does not have to be offered for such a supplication.

And Allah knows best.