Free will and marriage - Rambam

 Rambam (Shemona Perakim Perek 8) Men are, however, very often prone to err in supposing that many of their actions, in reality the result of their own free will, are forced upon them, as, for instance, marrying a certain woman, or acquiring a certain amount of money. Such a supposition is untrue. If a man marriesy a permitted woman legally, then she becomes his lawful wife, and if he does this for procreation  then he has done a mitzva. God, however, does not decree the fulfillment of a mitzva. If, on the other hand, a man has married a forbidden woman he has committed a sin. But God does not decree that a man shall sin.

Rambam (Teshuva #436): … For example the apparent contradiction to free will represented by the gemora which indicates that one’s spouse is predestined is to be understood as being dependent upon merit. In other words if this man or woman does a mitzva which gives them the merit of having such a spouse—then G‑d arranges that it happen that they marry each other. On the other hand if they so something which merits the punishment of having a marriage without peace and harmony—that will also occur…