Start out by saying: "I'd like to talk to you about how I'm feeling but I really don't want it to turn into an argument so I'm going to stay calm and just share my emotions with you while I hope that you can find it in yourself to understand while keeping calm as well."
... and then telling him how much you would like your grandmother to be in your life again as well as everything else about having date nights and time without the kid so that you feel the same excitement you had when you two were first dating and focused on one another.
“The willingness to accept responsibility for one’s own life is the source from which self-respect springs.” ~Joan Didion