As the other posters alluded to, curses do require a bit of skepticism, just because it is easy for coincidence, a pattern of bad decision making or depression to appear curse-like. However, if these don't apply to you though, the best way to gain some control over your situation is a bit of divination, i.e. tarot or the like. If that's not in your bag of tricks there are plenty out there that could help you out with that, and if you look hard enough you can find someone who will do it for free. (I am always skeptical of psychics, especially pay by the minute.) If the result points to some negative spiritual influence, you have a number of good options.
Talismans- You can buy or make these pretty easily. If you buy one though, I recommend performing ritual to purify, dedicate and empower it, because most you buy from magickal supply sites are mass produced and so won't have powerful effect without putting something of yourself into it. Making something of your own is always the most effective, but if you don't have the practical ability to do so there is no harm in buying something. Talismans are great for protection, but probably won't solve the problem.
Lifestyle changes- the previous posters covered this pretty thoroughly. The effects of embracing more positive experiences can't be stressed enough though. Curses feed on the misery they generate and become stronger; they are sinister that way.
Cleansing / Banishing rituals- These are worth doing regularly anyway, but especially if you suspect you are cursed. Banish any negative energy from your home, your work or anywhere you spend a lot of time and cleanse yourself to wash away any lingering malign energies.
Curse breaking- There are tons of curse breaking (or reversal if you are feeling vindictive, just prepare for consequences) floating around in books and online, Finding the source of the curse (which could be yourself) would be ideal, which divination could be helpful with as well. If the source remains unknown, the techniques I would lean toward are creating a sort of magical prison for the negative energy, or something like shamanistic self defense, that is to say, overcome the dark agents through sheer power. I am sure some people will disagree with me on that last point, but it seems that curses function on a similar way to haunting.
Hopefully some of those ideas inspire you! PM me if you want more specific advice, I dealt with a similar situation not to long ago.