His running
obsession may appears to be an innocent hobby, but it is likely to
be symbolic expression of an avoidance attachment type and/or
desire to remain in comfort zone. He might have personal issues
which he is afraid of diverging; that itself is already a difficult
process for any relationship to proceed further.
Running is a highly individualize activity; you do not require
anyone to do it with you technically. Hence, a core problem lies
with the need for too much 'me' time and too little 'we' time in a
non-negotiable manner.
One cannot choose to love deeply and still be invulnerable. The
very act of loving would naturally implore us to open up internally
and subject ourselves to a mix quantity of pain and pleasure.
During the time when he 'suddenly' go MIA, he is probably
contemplating if he should end the relationship. Selfish as it
might be, his lack of reasonable explanation for his behavior is a
likely indicator that he is not willing to make the choice to
terminate the relationship but resort to 'push factors' to drive
you away, insofar that you would make the choice to end it instead.
Therefore, ending the relationship on your side might be mere
formality.
P.S: At this juncture, what
you need is probably a man - not a boy that runs away (both
literally and metaphorically) the minute the reality of his
relationship confronts him. 
Cheers
Wow a female arm chair psychiatrist solving world's
problems.
HE likes to run and doesn't like this silly girl who just from
the posts annoys so much wallowing in self-pity.
Yes feminists, it's a convenient defition for wussies 'a real
man's responsibility to only to keep his bitch happy'.He's
following his passion ignoring an intruding woman and other odds in
his life, that makes him a real man.Now get a life!
http://manboobz.files.wordpress.com/2014/04/batmannn.jpg?w=604
