Why didn't he reply when he texted his girlfriend?

You can call her directly. If she doesn't want to reply, you can send her a more interesting message to make her happy. If she still doesn't reply, I think she probably doesn't want to, because she hasn't replied to so many messages you sent her, so don't send her any more, because she may not have seen so many messages you sent, so it's normal for her not to reply. Don't ask her again, because you have asked her so many times, she may not want to reply to your message, so don't bother her anymore, because the more you bother her, the more she may bother you. So I think you should stop texting her, because the more you send, the more likely she is to bother you.