If Bot was any good they'd have the place warded up and wouldn't be caught out and thus wouldn't need the help. If the enemy mid is roaming your mid should (most of the time) push hard and take their tower, it's not mid's fault that you have no map awareness.
If you get ganked a lot you're obviously doing something wrong.
You mean after he gets fed ganking bot, you're supposed to follow him and hope he doesn't turn around and instagib you and then proceed to kill bot, too? I'll do that. --- https://www.youtube.com/watch?v=KKM-XSYKrFo
If an opponent roams it's generally because they had full or near full health and have successfully pushed you away. Following can be really freaking dumb, only really advisable if they're going to reinforce a struggling lane and you might get a multikill out of it or you absolutely know you can not only catch them but beat them. --- If Pluto is not a planet Europe is just West Asia.