She's utterly countered by anyone who can either disable her immediately (Ryze, for example) or throw out a disable where her W return pad is after she's dashed in. Her strongest tool in lane is W>(recast)W>wait>Q, and she goes into melee range of your minions when doing that. Or, basically the same as the older version of LeBlanc.
If you're laning as a squishy champion (or not buying any MR) and not playing around LeBlanc of course she's going to be overbearing. Just like laning against Ahri and not making any effort to dodge her skillshots.