Each provider is different so I can't speak specifically as to Verizon. However, I can certainly provide some direction.
Your fiance certainly has no legal ability to get your texts on her own, so that is not an issue.
As to the attorney, he would need to issue a subpoena for the records. With no pending litigation, it would be difficult for him to issue a subpoena. Additionally, most providers only save text messages for a brief period of time, typically 10 days. So, if the text messages in question are at least 10 days old, you should be in excellent shape.
As far as "hacking" into your cell, this can only be done by law enforcement and even that would require a warrant. Based on the facts as you've provided them, that is simply not going to happen in your situation. The attorney has no lawful ability to hack your cell phone. If he did so, the Bar Association would most likely consider that to be unethical behavior and could suspend his Bar license, meaning he would have no ability to practice law. As such, I would have no concern that the attorney might try to hack your phone.
BotXXXXX XXXXXne, while I can most certainly appreciate your concern, the facts here seem unlikely to lead to your fiance having the ability to obtain your text messages.
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