Messages in inbox still show when deleted by creator

**Describe the bug**

If creator deletes a comment that shows in your inbox, it will still show the comment. Should say "deleted by creator" or something.

**To Reproduce**
Steps to reproduce the behavior:

1. User A create comment reply to user B
2. User A delete comment
3. User B views inbox
4. See comment content intact

**Expected behavior**

Should not be visible.