To start off, winning your ex back is not impossible but you'll need to know what works best first and what doesn't.
Doing the wrong things won't help you when it comes to this, especially if you are the only one who's interested in saving the relationship.
So what do you do in order for you to make her change her mind so that you two can get back together like you used to? Well, you'll have to look into a few things that don't work.
You'll always be one step ahead by avoiding them.
The first thing is that you shouldn't think that by only giving her some flowers you'll win her back.
This is especially aimed if the reason for the breakup was because you've done something terribly wrong in the first place.
So don't expect flowers to do wonders.
Also you'll have to avoid pestering her.
Just because you are appearing in front of her out there doesn't mean that she'll be glad to have you back.
For instance, you shouldn't call her over and over because it only pushes her further away.
And if she has been avoiding you recently, you should avoid doing that especially.
Don't ever give her the impression that you are needy and desperate.
It will only make you appear undesirable and push her even further away than she already is.