What is Roderigo complaining about in the opening scene of Othello?

In Act I of Othello, Roderigo
complains to Iago that he is paying Iago money to get Desdemona to love and marry him,
and--so far--it has not worked:

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Tush! never tell me; I take it much
unkindly
That thou, Iago, who hast had my
purse
As if the strings were thine, shouldst know of
this.

Roderigo is
now poor and brideless.  Brabantio has previously denied Roderigo as a suitor for his
daughter, and now Roderigo cannot believe that Iago knows about Desdemona's elopement.
 You see, Roderigo is nothing short of a whiner, and he cannot believe that this beauty,
the daughter of Venitian senator no less, would choose to secretly marry an older Black
man over him.

Also, Roderigo will serve as Iago's
mouthpiece as they both complain to Desdemona's father outside his home.  Under cover of
night, Roderigo will wake up the Senator and tell him that his daughter has
eloped.