You're not in the best mind frame to meet someone special or make a satisfying connection during this three-week transit, because pessimism and idealism will both stand in the way of seeing someone for who they are and accepting them realistically. Due to your negative outlook during this time, you'll subconsciously attract people who aren't worth your time and attention. You might find out that someone you were interested in actually lied to you about themselves or their availability, or that they just weren't entirely straightforward with you about something.
The discovery will hurt, and will only increase your feelings of doubt and pessimism about love in general. But just because one person does that kind of thing doesn't mean everyone will. In this case, one bad apple shouldn't spoil the whole bunch. Don't let it affect your hopes for the future. It's even possible that this person didn't really lie to you -- that you, in fact, failed to read their signals correctly, because you're not in the clearest frame of mind during this period. A word of caution: If you do go out on a date now, avoid drinking dates. You're more susceptible than usual to alcohol.