The word "commitment" can have some ominous undertones, perhaps because it is often associated with phrases like "being commited to an asylum" or "committing a crime". Both might indicate a loss of control. But commitment in the sense you seem to be referring to need not bring that sense of danger with it.
Commitment, in the sense of self-investment in a project, represents nothing but a connected cluster of decisions. In that way, it represents not a negation of freedom, but an exercise of it. Although it might seem safer, the tendency to dither and concern oneself solely with the basic concerns necessary for survival seems as unsatisfactory as making a mistaken commitment. The old cliche of "even choosing not to make a choice, etc. etc..."
And of course, the word "commitment" need not signal an inexorable movement. The nature of the project will determine the qualities of the commitment, and some thresholds cannot be uncrossed. But that being said, there are few projects that do not allow one to revise one's opinion and make new choices, diverge from the project at hand.
The discomfort associated with a new commitment seems to me less a symptom of the loss of freedom, and more a sense of uncertainty regarding the value of one's choices and one's capacity to live with them.