When is it okay to give up on your dreams?

Hey

I miss writing, I'll be honest with you. So I decided I will make this little platform alive again.
Plus the timing is just perfect, because I have many exams to write but instead I'm here.

I came across an interesting video on Youtube the other night (when I was supposed to write an exam again, but oh well).  https://www.youtube.com/watch?v=4CuJcetUxT4&feature=share
A short video about self love and self worth, and how negative self talk affects you (me, you get the idea). But that's not quite what I want to write about, or what has driven me back to officially writing at the first place and . That would be a long, night conversation which I had with my best friend about taking risks 
and being harsh to achieve something.

And honestly, I want to hear your opinions. I've always been a passionate risk-taker, I mean look at me, living in a different country since the age of 18, it doesn't get better than that does it? I am a person who would never say no to any sort of adventure, to any sort of challenge mostly just for the sake of it. Your comfort zone is a great place to stay in, it truly is. As Mr. Bukowski put it: You can't beat death, but you can beat death in life. If you're going to try, go all the way, otherwise don't even try. There is no other feeling like that. You will be alone with the gods, and the nights will flame with fire. You will ride life straight to perfect laughter. It’s the only good fight there is.

And I must say 21 years old me very much agrees with all of this, as the hopeless idealist and romantic didn't have the chance to die yet, and I'm very familiar with the concept of trying all the way, but my question is when is it worth it? As if, where is the line of something being not worth your efforts? When is it okay to give up on your dreams?
When is it okay (I love this expression) to just run away and never come back?

Now, I'm not smart but my friend actually told me something extremely interesting. You don't give up. You fall and fail, you keep on getting dissapointed and you keep crying over it, but you keep fighting for what you really want. And the reward she said is your own growth and change and maturity. 
In the moment I would literally do anything, anything to present a contraargument. If your dream takes too much effort maybe it isn't for you at the first place. Maybe it's better to just find something else to focus on. A different goal, a different job, a different person to put your energy.
Because you can only take as much, because your self worth can only take as much.

I'm being very philosophical and perhaps annoying you, so I'll go straight to what I think is my point with this post. I want this blog to turn into a journal that I want to share with you. It's been a while I did something out of my comfort zone and opening up publicly is definitely it. 
In the course of the past month I learned a very interesting lesson and perhaps an answer to the problem my friend and I talked about. When is it okay to give up on your dreams? The answer would be when your dreams stop you from growing as a person. 
When you chase an idea, that does you harm.
When you chase a toxic person, who makes you doubt your own worth. 

Have a good day and please, tell me what you think!
We can have a little discussion ;)

P.S. Pics are a liiitle bit off, but it's finally spring and it's so pretty here!!