Growing Apart

I've been with my man for 4 years now and we have a beautiful son together who is just over a year old. Lately over the past few months I feel as if my relationship with my honey has taken a drop. This year has been extremely tough on us, we've had financial problems as well as I have experienced a tragic loss in my family.  I don't know what the deal is but we just don't seem to click anymore. The spark is gone. We are rarely affectionate, I feel as if our fights have escalated to an all time high, sex is non existent, I just don't know what to do!!! It makes me so sad to think that we are nearing the end of our relationship. I want my son to have a family but I just don't know what's going to happen anymore with me and his father. HELP!!! Any advice on how to pick my relationship up? Or should I really be considering the option of our relationship ending?