1) Prioritize. Exactly what is giving you trouble in your life? Why is the current situation a problem? What is the root cause of it? What can you realistically do to make it better?
2) Focus on yourself first. If your life feels out of control, you need to get yourself sorted out first before you add in a significant other. This is a time to be a little selfish, and do what's best for you before focusing on others.
3) Look to the hierarchy of needs. Do you have a roof over your head and enough food that you aren't going to bed malnourished? If not, contact your local social services department, and they can direct you to resources for low income housing, food banks, etc. Do you have a medical condition that needs treatment? If yes, again your social services department should be able to refer you to a free clinic and/or assist you in applying for Medicaid.
Once you have food, shelter, and basic medical care, you can look to other possibilities that may be causing you substantial difficulties. Depression affects a lot of people, and is not always diagnosed; if you are feeling lethargic or hopeless or apathetic it's possible that it's a chemical imbalance your doctor can help with. Alcohol is also a problem for many--individuals may think that it helps them escape, but it more often makes things worse.
4) If you're hitting a dead end professionally, try to identify why it is. Are you in a profession that there's too much competition and luck plays a major role in success (eg, music)? Are you in one that you just kind of fell into but hate? Did you get into a profession for the money but find out that it's not necessarily there? Do you feel your career is a dead-end one which will not allow you to have the sort of life you want long-term? In these cases, you may well want to consider going back to school -- even part time at a community college -- to get specific training for another field which you would enjoy more and/or is more reliable, and meets whatever salary range you think is important for what you want in life. Is it that you don't feel fulfilled by your job? Many people don't, but look for fulfillment through other avenues, such as volunteer work. Finding a different outlet for your desire for meaning and fulfillment can take a lot of the pressure off of the job. If you have the education but are having difficulty finding employment, contact your college/university alumni resource center and ask for help on finding interviews in your field, aid in improving your resume or your interviewing skills, contacts from the alumni network who may know of openings in your field, etc.
5) I just mentioned volunteer work, so I'll hit it again here; it can alleviate a lot of problems of modern life, so long as it's something you choose because you are interested in it. If you are feeling disconnected from family and friends, it will give you a group of other people to interact with who share at least some common interest, as they all chose to help feed the poor/spend time with the elderly/build a home through Habitat for Humanity/care for the animals at the human society shelter/teach adult literacy classes at the library/whatever. Projects like Habitat or cleaning up a section of a park or the like can also give you a direct accomplishment--you can look over your work and see the direct effect of the past few hours of your work.
6) If you've got all that together, and think you have the energy and time to date but aren't getting anywhere, consider asking a trusted friend to give you an honest evaluation of why (s)he thinks you're having trouble -- and don't get angry or defensive about whatever you're told. If you can't or don't want to do that, make sure that you have hobbies and activities that you enjoy, and which you could conceivable talk about with others. These make you more interesting, a better conversationalist, and increase your confidence, all of which are attractive qualities. This also can tie into point 5 above; I know a man who took up gourmet cooking as a hobby because he was a lawyer working mostly in matrimonial law, and his cases took forever to resolve. With his cooking, he could spend a couple of hours and have something to show for it. Further, these hobbies will put you into contact with others with shared interests, always an important thing for dating. After all, the most important factor in dating is meeting potentially compatible people in the first place. As a guy in his 20s in NYC, virtually any hobby you can think of you can probably find a group into it, and quite possibly even a gay group into it.
7) Whatever changes you want to make, formulate them as a step-by-step plan of things you can check off once they're done. Most people will find it far easier to make 100 small changes than one big one. Instead of "Today I'll clean the house", consider "Every day, I will clean up the mess I make that day. Today, I will also clean the refrigerator. Tomorrow, I will clean the counters. The next day, I will scrub the bath tub..." Sure, it may take you a few weeks to get the whole house clean, but you'll still get there. The same goes for any diet or exercise plan, for getting your financial health in order, whatever.