Kimmerz, I wouldn't accept the request for allowing alerts to be sent to texters who have sent you messages that you have read their texts. This is very similiar to what you can do w/emails when you send messages because this allows you to know when they have openned their email messages from you.
I would agree w/your friend...your xh sent the request. Apparently your xh wants to know the minute you "open" your text messages and have read them from him.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.