Definitions of marital privilege
the right for all words and acts between husbands and wives to remain confidential during trials. The exception to this right is during trials where one spouse is against the other, such as during divorce proceedings.
Civil partners cannot enjoy the confidence of the marital privilege.
the right of a spouse not to give evidence against their husband or wife during a criminal trial
Since you are married, your wife may claim her marital privilege and refuse to testify against you.