I'm sad to hear this but I think some perspective is needed.
First, graduate school - especially PhD programs - is not the 'natural' next-step for psychology graduates. If you are a senior, you are competing with people with advanced degrees, work experience, or those with extra years off doing full-time research. These people have anywhere from 50% more to double your experience, knowledge, and expertise. Unless you are an absolute rock star and very lucky, not getting into a PhD program as a senior in college is the norm, not the exception.
Based on my observation in mid-tier+ I/O programs, I would say that less than half of the incoming students are "straight out of undergraduate". 1/3 typically have masters in I/O, 1/3 will have some combination of relevant work experience and/or extra years doing research. On top of that, most reputable programs accept like 5~10% of applicants, and most of those applicants are usually top 10~15% of their class. So people that get in, are often literally one of the best undergraduates in their University.
And how many decent Ph.D. I/O programs are there in the US? SIOP shows me 70 programs, and taking out some slightly sketch ones, there are maybe 40~50? At an average of 4 incoming students per class, thats 200 students. Thats smaller than my Intro to Psych class.
So, if you really, truly want a PhD, take the gap year, get a masters, beef up your research, work hard. There is literally nothing to be ashamed of. One round of rejection is nothing compare to what you will face in grad school