A very important part of the play to consider in regard to this question is Act V scene 2, when Othello kills himself, but before he does this, he delivers a speech which clearly shows the way that he regards himself and also presents some sort of justification for taking his own life. This is what he says:
Then must you speak
Of one that loved not wisely but too well,
Of one not easily jealous but, being wrought,
Perplexed in the extreme; of one whose hand,
Like the base Indian, threw a pearl away
Richer than all his tribe; of one whose subdued eyes,
Albeit unused to the melting mood,
Drop tears as fast as the Arabian trees
Their medicinable gum. Set you down this,
And say besides that in Aleppo once,
Where a malignant and a turbaned Turk
Beat a Venetian and traduced the state,
I took by th’ throat the circumcised dog
And smote him thus.
Othello initially talks of how he wants to be remembered. What is fascinating about this speech however is the way that Othello recognises his strengths, which he sees as military prowess and bravery, but also he identifies himself as an outsider in Venetian society, as he occupies a position where he is both accepted and rejected by Venice. The fact that he chooses to kill himself the way that he once killed a "turbaned Turk" shows that ultimately, as a result of what has happened in the play, Othello identifies himself as an enemy of Venice and as a result his last act in the play is to rid Venice of another of its foes: himself. The self-perception of Othello is therefore greatly impacted by the events of the play, as Othello comes to regard himself as a threat to civilised order.