The translation is correct. The word is appropriate to the image which follows, in which Paul represents himself as the marriage-friend who has betrothed the bride to the bridegroom, and consequently shares the bridegroom's jealousy of his bride (see on Joh 3:29). Compare the Old-Testament passages in which God is represented as the spouse of His people: Isa 54:5; Isa 62:5; Jer 3:1; Eze 16:8; Hos 2:18, Hos 2:19. For the different senses of the word, see on envying, Jam 3:14. Theodoret's comment on the passage is: “I was your wooer for your husband, and the mediator of your marriage; through me you received the bridegroom's gifts; wherefore I am now affected with jealousy.”
I have espoused (ἡρμοσάμην)
Only here in the New Testament. Lit., have fitted together. Used in the classics of carpenter's or joiner's work; of arranging music, tuning instruments, and fitting clothes or armor. As here, of betrothing or taking to wife. The Septuagint usage is substantially the same.