Aaaa affairs of the heart always hit us hard. Sending giant hugs your way. It sounds like you love to ride so keep it up. Sometimes it can be hard to see all the good stuff in our lives when the bad stuff is there too but look closely and you will see all you have to be happy about. Hug your boy, pat your dog and dont give that ex a thought.
Tell yourself if he left then its his HUGE loss not yours. You obviously have heaps to offer so save your energy for someone who sees that.
Good luck with the training and let us know how you are getting along.
The most effective way to do it, is to do it.
Amelia Earhart
2005 Trek 5000 road/Avocet 02 40W
2006 Colnago C50 road/SSM Atola
2005 SC Juliana SL mtb/WTB Laser V