“You carried it alone as long as you could, and then you weren't strong enough to take it any longer. You kept fighting everything, and everything broke you down, until in the end you were just a little goddam bolt holding on and squealing when the machine went too fast.”

Wenn du einen vielbetretenen Weg lange gehst, so gehst du ihn endlich allein.
Source: Aphorisms (1880/1893), p. 28.

Old Town Folks (1869) Ch. 39 (p. 507) Sometimes paraphrased: "When you get into a tight place and everything goes against you, till it seems as though you could not hang on a minute longer, never give up then, for that is just the place and time that the tide will turn." and "Never give up, for that is just the place and time that the tide will turn".
Context: When you get into a tight place, and everything goes against you till it seems as if you could n't hold on a minute longer, never give up then, for that 's just the place and time that the tide 'll turn. Never trust to prayer without using every means in your power, and never use the means without trusting in prayer. Get your evidences of grace by pressing forward to the mark, and not by groping with a lantern after the boundary-lines, — and so, boys, go, and God bless you!

Source: King Solomon's Mines (1885), Chapter 5, "Our March into the Desert"

Gerald Ford in a Presidential address to a joint session of Congress (12 August 1974)
Ford has also been quoted as having made a similar statement many years earlier, as a representative to the US Congress: "If the government is big enough to give you everything you want, it is big enough to take away everything you have."
"If Elected, I Promise…" : Stories and Gems of Wisdom by and About Politicians (1960) p. 193
Unsourced variants attributed to Goldwater include:
A government that is big enough to give you all you want is big enough to take it all away.
Remember that a government big enough to give you everything you want is also big enough to take away everything you have.
However, Karl Hess, a speechwriter for Goldwater, quoted Goldwater as having "repeatedly" said during the 1964 campaign that "the government strong enough to give you what you want is strong enough to take it all away." See The Death of Politics http://fare.tunes.org/books/Hess/dop.html, a Playboy article from 1969.
Misattributed

Presidential address to a joint session of Congress (12 August 1974)
Ford has also been quoted as having made a similar statement many years earlier, as a representative to the US Congress: "If the government is big enough to give you everything you want, it is big enough to take away everything you have."
"If Elected, I Promise…" : Stories and Gems of Wisdom by and About Politicians (1960) p. 193
Similar assertions have often been attributed to Barry Goldwater and Ronald Reagan. Some of the inspiration for such expressions may lie in "The Criminality of the State" by Albert Jay Nock in American Mercury (March 1939) where he stated: "You get the same order of criminality from any State to which you give power to exercise it; and whatever power you give the State to do things for you carries with it the equivalent power to do things to you."
1970s, Address to Congress (12 August 1974)

Attributed to Reagan from informal remarks to reporters 10 October 1984,and to students and faculty at St. John's University 28 March 1985.[citation needed] The statement was made a decade earlier by Gerald Ford in an address to a Joint Session of the Congress, 12 August 1974. It is sometimes attributed to Thomas Jefferson and Barry Goldwater.
Similar assertions have often been attributed to Barry Goldwater. Some of the inspiration for such expressions may lie in "The Criminality of the State" by Albert Jay Nock in American Mercury (March 1939) where he stated: "You get the same order of criminality from any State to which you give power to exercise it; and whatever power you give the State to do things for you carries with it the equivalent power to do things to you."
Misattributed
Variant: A government that is big enough to give you everything you want is also big enough to take everything you have.

Source: Life, the Truth, and Being Free (2010), p. 124

Source: Just Listen

Source: Hardboiled Wonderland and the End of the World (1985), Chapter 24: Shadow Grounds