Shakib's personal life is his personal business. Those who are making a fuss about the image, has nothing better to do other than gossip on other's personal business. It doesn't matter even if that image was genuine.
But the fact is that the image is 100% fake. Unfortunately, we are easily fooled. The viral status of the image is just intolerable. Saw it in lot of people's status updates within last few days! I had enough.
The image in question was photoshopped pretty nicely. It can easily pass as genuine to untrained eyes. If you have done photoshop effects you should be able to pick up subtle imperfections. Even from a distance you can easily notice that the lighting itself is flawed (compare light source on Shakib's face/body and the girl's face/body). The image has been released at low resolution to hide lot of imperfections.
Sometimes you just need to put things under the lens. Take a look and judge for yourself.