Just a random question! Txting an ex on her birthday? Good or bad idea?

It rather depends on what you want to gain from it.

Honest and simply, no. Don't

Either you are texting her because you want something sex, restart your relationship or attention. Maybe a mixture of the above. Generally unless people have kids or mutual friends eventually contact breaks down, exes are exes for a reason and any contact will cause disappointment to either you or her depending on your situation.

The fact you are asking the question means you should have her number deleted and any other possibilities of finding it out erased (texts, phone log, friends deleting it) then you should have her blocked on fb, email deleted and blocked. If there are friends of yours who continue to interact with her then consider blocking them or at least deleting them from FB. Explain to them why too, you can probably be cool with them as you have a legit reason.

Then take up some hobbies or do something to improve your life (new project, new job, promotion, travel) and go find a tonne of other girls. Make it daily to keep your mind off her, trust me once you have even one new girl you will forget your ex.

We've seen this type of post many many times. I have given you the best possible advice anyone could give you. I know, I know I'm great but I'm a regular guy like any- nah I'm great. Cheers.

FFS make an effort mate! How are we supposed to give you any kind of informed advice when you give no context whatsoever?

If this girl was the great love of your life, you've chased the field for ages and still want her back, then yes, yes you should. If she's just an ex, then no, no you shouldn't.

In general the chances of it being a good idea are very slim. The chances of you regretting it in 6 months time tho, are very high.