Tell me what on earth possesses people to run from a fight when it is 2v1 (you have the 2), they are not even taking any damage,
So.. the guy was already heading to town to buy something and you spotted a DG on a nearby lane and charged them without saying anything to the "noob teamate" who "ran away" to town eh? Then got all angry cause he did not bother to read your mind.
If you see a 1 vs 1 and are near, and you are, id say above 50% health, you go to it. Mabey even less.
Even if it was only to scare the other god away and get the flag or summing, or get your buddy out!
You have a mini map, and should always be zoomed out far enough to keep an eye on incoming Dg, its not hard to spot a fight.
Added to that, typing when your in a losing fight can be tricky, so i see no reason to defend a dg who walkes away, to town, with full health when your buddy is taking a beating.
No mana is not a good reason since in a 2 vs 1 your auto attack will be enough to make a difference.
Thats what i think...