Is this Depression? Others, it dorsnt.

Hi. I have a good job that pays me well. I have a good set of team mates and friends around me. I got married to a friend two and a half years back. He lives in the US and I do not have a work visa for US. I have my dreams and don't want to be a homemaker. I continued with my job and we both had been traveling to and fro whenever possible. All in all it all seems to be fine. The problem creeps in over the weekends when I am alone. I feel depressed and lonely. I cry more often and thoughts about death hover over my mind. By death, I do not mean that I am suicidal but I feel like it's all a waste of time when we know it's eventually going to end. I do not like some of his family members and thoughts about them lingers on my mind. I feel helpless and sick since I am not capable of doing anything to solve this situation. I ruminate those bad encounters and feel bad. I tried joing physical training classes to ease my mind. In certain days, it works wonders and on others, it dorsnt.