It really is context dependent.
If you freeze and happily resume farming while opponent is active on map, you are definitely in the wrong, there has to be some response from you that punishes the roam in some way.
Now you have to get something done while he is gone. Steal a scuttle. Rob a camp. Ward a buff, push the tower. Will your side lane stall as the noob talon is waiting on a ward for the wave to crash the tower? maybe you want to join and turn a gank into a team fight? You need jungler there? ping him now, and wait for him to be on way before heading out?
Or maybe counter roam? Talon wants to kill bot lane? sure, have him deal with the fed jax you've set up in top lane, see how he likes it.
You have to have some kind of plan, to get an advantage against your lane opponent. Can't leave it to the ineptitude of your team mates. Especially if they are ahead and you are behind, the worse thing for them is your opponent interrupting their winning.
To conclude, i don't know exactly what you should do. But if you just kept last hitting with autos as your opponent roamed? you didn't do that something.