"...I'll then see a little video or something has been sent to me by a friend on my phone. I unplug the headphones from my macbook, plug them into my phone, watch the video..."
Why don't you just watch the video on your laptop? Even with a simple 3.5mm plug, moving the headphones over sounds like a lot of work for something that you can just do on the laptop.
Even if your friends send you an SMS with the video, there are plenty of ways to get an SMS on your laptop.