<human>: Can you provide a brief overview of the text?

Hello Reddit. Just trying to figure out my status. I am from Canada and currently working in the US (Texas) I applied for TN at the border but was denied because my diploma was not entirely in related field. Now I was working remotely for the company until I was called for a project in July. At that point the Customs Officer put a date of return on my passport of August 15. When I got here the project was extended and the company hired a lawyer for my case. The lawyer submitted the I-129 petition for TN visa in july. Since then we have been waiting for a reply. It was supposed to take 2 months but now it has surpassed 5 months. 

Now here is the situation. My Brothers wedding is in Canada on Jan 3 and when I emailed the lawyer is it ok for me to go attend that he is saying that now if I leave the country my visa petition would be considered abondoned. Just looking for advice if thats true and if there is a way for me to still go.
<bot>: came to US from Canada applied for TN with an I-129 and now lawyer said that I can't leave or else my visa process is going to be abondoned.