It's funny, I've just come off the phone to an MD who hired me in my first role nearly 20 years ago. The man is a living legend and although we are far from friends or pals, I did spend 20mins listening to his view on a particular topic. Do I agree with it all? No. Was he expecting anything in return? No. Did he get anything from it? Unlikely. Was a worth while call - absolutely.
The problem with 'Mentors' is that they mean different things to different people. I did a long winded reply to somebody a while back when they posed the same question. You might be better off compartmentalising the problems and then seeking help for each one. If you are feeling low in mood and self-worth, speak to a GP/Therapist etc. If it is a business related problem, seek the advice of various friends/colleagues/business leaders and draw your own conclusions.
A mentor doesn't give you answers. A mentor helps you figure out the answers for yourself and supports your decision making/ allows you to confined issues and concerns and helps you overcome problems. They will not lead you or your business out of a rut - that has to come from you. Mentors also don't expect much in return (perhaps doing things when you say you will and continuing a mutual trust/confidentiality etc), but certainly are not expecting you to offer up gems or wisdom that will benefit them.
At times like this, I would get a piece of paper and a pen, sit in a quiet room and jot down the individual problems (the real ones) and draw a line off each to a potential solution. Make a plan to overcome or combat each problem and then get to it. It might be painful, it might be long-winded, it might even require doing things you never thought you ever would, but you should give it a go.
If you do go looking for a mentor, don't pay for it, don't expect too much and do be prepared to put in the effort. If you are lucky enough to find a good one, you are extremely fortunate. Otherwise, back yourself, grab this issues by the proverbials and do something positive about them.
Good luck and go get it...!