Wiktionary
vb. (context idiomatic English) To put up with something; to deal with something, such as pain or misfortune, without complaining.
Wikipedia
Suck It Up is a young adult novel about a misfit, vegan, teenage vampire named Morning McCobb. It was written by Brian Meehl and published by Delacorte Books on May 13, 2008. It won the School Library Journal's award for "Best First Kiss".
Usage examples of "suck it up".
The desiccated tissues seemed to suck it up instantly, yet nothing had ever tasted half so wonderful.
It was of course meant to spray water, not suck it up, but a vacuum pump had neatly reversed its function.
They suck it up, do the job, and don't go around looking for somebody to pat their head and say, 'There, there.
As a further matter of fact, she was in it now, and decided to just suck it up, the way a kid got rid of too much Halloween candy on November first.