What do you do when this happens??

cry and be depressed for a couple of hours... then do something else until my ap fills back up (about 10.5 hours) then play fgo some more cuz i enjoy this game, cuz it is in fact a game and is nothing to get worked up over.

go through the 5 stages of grief lol

i don't necessarily take a break, i just get hella mad and when i eventually accept it after ranting about it to anyone i possibly can i'll just move on and hope (though it's probably FOOLS hope) for another chance

I typically binge eat on chocolate or sweets. XD

Then I go back to the game and farm the hell out of whatever free quest I need to take out my frustrations.

nothing...play this game for long enough and your expectations will naturally adjust to reality.
After a while you just automatically expect crap in every roll, and if once in a blue moon you land into something good is just a pleasant surprise.

I mean just think about it. Gatcha rates for 5 stars are 1% so right away you should come into the gatcha expecting not much good. If you come in with low expectations, you wont be as sad. If you like playing the game soley for the want to pull the best servants your going to get disappointed pretty quick.

Also, just because the odds are 1%, that doesn't mean you can expect a success every 100 rolls. While unlikely, there will be someone out there who doesn't get a 5* in 1000 rolls. In a game I've played, there was a roll with a 20% chance and people complained when they failed 20 times in a row. I simulated it with a program, and about every million or so times, it would take more than 60 rolls to succeed. Such is RNG...

It hurts more when a friend of yours, who barely wants the servant, gets it in a few tickets. But yeah like everyone else said just wallow in despair and keep playing. They wont disappear forever you probably have another shot in the far future so until then just wait and hope. And in the off chance you fail again well... that cant possibly be the only servant you want right?

Controlling the salt huh? Well when I don't get the servant I want I just go and look at my Saber Alter lvl 90 10/6/10 np2 and think "you are all I need"...and then just play again xd

Flip one or wo table and than continue to play the game. Hadn't good JAlter and Merlin.... But I got Jack and Gramps, so it is somewhat even now

I have gone through that as well, i just grab my guitar and do some singing after that play FGO again and doing some solos.

Also continue to save SQs.

I take my wallet out

Never save sq, spend them on every interesting banner. Keeps expectations low. Rate up is a complete lie anyway.

I will just release all the anger and resentment then after a while I'm thinking that maybe I got all I wanted. Like for instance that I didn't get Musashi and Merlin then I remember that I have raikou and Ishtar on my team and they both carry me throughout the game in a long run