What is the version of the following sentence with correct punctuation?

The problem is that you may not fully realise that it is you yourself who are changing You may blame your unhappiness on a loved one who seems to be moving away from you or seeking affection elsewhere
The problem is that you may not fully realise that it is you yourself who are changing. You may blame your unhappiness on a loved one who seems to be moving away from you or seeking affection elsewhere.