I have successfully resolved such problem.
The crucial moment here was in creation of many-to-many relationships between this domain entities.
So as a result i have injected to each concrete domain model property(collection of related entity).
For example, in domain model of
Message
i have injected such property:
public virtual ICollection<user> UsersWhoRead {get;set;}</user>
As concerns mappings, i have added few lines of code:
this.HasMany(x => x.ReadMessages).WithMany(x => x.UsersWhoRead)
.Map(m => m.MapLeftKey("User_Key").MapRightKey("Message_Key").ToTable("UserReadMessage"));