30 and lost. Failed at my marketing career. Any advice?

I've been trying to make a career in marketing happen for the last 3 years, during that time I have been fired 4 times due to lack of experience, 1 I quit because the company was bad (my former boss is literally a felon now) and the one job I was able to keep for a year and a half ? a government job I'm pretty sure they only kept me to not lose on that government sponsorship money. I am so tired and so lost, before that I have only managed to work in call centers and retail. I am open to doing something else like working with animals but I just.. don't know what to do. Please help. - I have a college diploma in marketing but I am willing to go back to school.