ditto on the "give it time" and equally "you will get there!!!!!" I am 50 and have never quit exercising of my own accord but have come back from injuries and a bad car wreck. Healing and improved fitness come more slowly with every passing year.

I would add one tip to cycling speed: RPM! working on speed of leg turnover and smoothness of pedal stroke can really improve your speed- a lot of folks try to mash along in too high of a gear. Once you crank up your RPM and have built up strength, then you can pedal fast in a high gear and keep up with anyone (: