I'm sorry you feel lonely
I know how it can be as my husband works 18 hour shifts and my boyfriend is a long-distance relationship (and his shifts can be just as long).
I hope you find ways to keep busy, it usually helps me if I do things for them (whether it's chores and feels like I'm doing it partially for my husband, partially for me, or working on a gift for one of them, or planning out our future and projects, etc).
It's a bit harder for you I assume since Joshua is deployed and therefore not around (so chores probably feel less like they have anything to do with him) and your situation with M is "on hold" so projects are hard to make... But I hope you can find something that will work for you!