How can I get involved in the labor movement without a normal job? (Pennsylvania)

I'm a 44 year old woman who has worked more jobs than anyone I know. From grunt work to professional. I went back to school as an adult and became a state licensed Physical Therapist Assistant. But have had many different career paths since then and beforehand. Currently I work for myself doing some freelance copywriting and other project based stuff. I have applied for union organizing jobs with the SEIU three times. Always rejected. It seems everyone's answer to get some experience is organize your workplace. Which I don't have and don't plan to return to. In fact the only "normal" job I think I'd ever want to return to is helping other workers unionize. This isn't like I'm some college grad with no real world working experience either. I've done it all. Truly. And I know what's out there. I think my broad and varied experience means Id have something to offer in the space, but I can't seem to wiggle my way in. I don't make alot of money so expensive research programs are not an option, but I'd be open to some study if it was affordable. I will admit my research hasn't been too extensive yet, so here I am. Any advice on how to get involved in the space without a traditional job?