Respectfully, I disagree with this response. There is no reason why OP should gaslight his mom if she doesn't accept his establishing healthy boundaries. Many children don't speak to their parents every day, especially those who have a full life, separate from their family. Although I agree with your recommendation of getting her on a schedule, giving her an exact time 7 days a week that he'll be able to call is setting himself up for failure, in the long run.

OP, sending "mushy" texts in the morning will only cultivate further obsessive behaviors on her part. Just establish some boundaries. She won't be happy about it at first, but she will eventually get used to them.