This question has been asked many times I'm sure but I've attached a sketch of my condition... can any when tell me if this will work? Or should I use the standard washing machine p-trap assembly? I just thought it would be better to have the washing machine drain into it's own 2" line then almost directly to the 2" waste at the wall.

Your drawing looks like it should work. The stand pipe should be at least 33" tall. If you ever get any backup up you can add a water tght collar at the top but this rarely is needed. Some new Maytag washer pump a lot of water and can cause even a 2" pipe to back up with no clog or restriction in the pipe.

This question has been asked many times i'm sure but I've attached a sketch of my condition...can any when tell me if this will work? or should i use the standard washing machine p-trap assembly? I just thought it would be better to have the washing machine drain into it's own 2" line then almost directly to the 2" waste at the wall.
I have done a similar set up like your drawing and it works fine, when I set up mine I figured that when the water begins to go through the waste water line it would create suction and draw the water away from the bathroom sink, and it does.

This set up should drain OK. My only concern is the elevation of the sink. A partial clog or a high output washer pump, such as a Maytag, could force the discharge back up through the sink. HGor high is the sinks rim in relationship to the washer stand pipe. If this does occur do you have a way to seal off the sink? That would solve the problem. Good luck, Tom