Linking bidirectional process flow diagram to Excel data

[dlFHG]

Hi guys.  I'm fairly new to Visio and have been consuming as many tutorials as I can, however, I haven't been able to find anything on linking Excel to Visio beyond basic Org charts and simple flow diagrams.  What I would like to do is take an Excel task analysis that has a column for the task step number and and another for the interaction between workers to build a Visio structure that has connecting arrows traveling both ways between entities and can have multiple arrows into a single entity. 

I have attached a simplified Excel sheet of what the input will look like and a Visio drawing of the desired output.  Could any of you help me on the path to accomplish this?  Thanks

[Yacine]

If you would upload the visio file as 2007 version I would have a look.