The more you write, and the more you submit, the more likely that you will be able to make a career out of what others can only afford as a hobby. It's a law of percentages. If you enjoy writing but are terrified to submit, you will not see your name in print nor will you earn an income. It's that simple. Likewise, if you write only one article a month, and submit, that only gives you 12 opportunities a year to earn a return.
Rejection is part of the process of writing.
It's not personal. Just keep repeating that phrase - it's not personal. And send out another query, another article, another letter asking for guidelines. It may come as a shock but they are actually looking for good, well-written pieces from individuals just like yourself. They are also looking for professionalism.