You have certainly found yourself in a big confusion with forwarded emails in your email client. Since many people use Gmail for their default email client, Google is about to make forwarding easier.
The newest feature, scheduled for January 21 will let you forward an email you’ve received as the attachment, which will make things easier, and reduce the mess.
Also, sending emails as attachments will let you write a summary message to your recipients, which will help them with content. The attachments can be opened directly in their own email clients since every attached email will behave as a file with the “.eml” extension. You will be able to attach as many emails as you want. When you click it, it will open in a new window.