Happiness is contagious. Have you ever talked to someone who is feeling down and frustrated with life and felt it rub off on you? Have you walked away from a conversation with an unhappy person and started thinking about all the things that are wrong with your life?
It sounds cliché but you need to surround yourself with like-minded happy people.
Lets be honest, this can be hard at times as there are always going to be situations where you cannot escape daily interactions with unhappy and frustrated people. Such as the workplace where there are always people frustrated at one another or at a situation they have been put in and may spend time complaining to you about how unfair it all is. These interactions are unavoidable, but the way you decided to deal with them is.
I find the best way to deal with this is to have a separation between your workplace and your social life. If you catch up with people you work with outside of work you always find you end up only talking or really complaining about work. This is not a good environment to be in and can change your opinions thoughts about work, and more importantly negative thoughts about work.
Just keep work for work.
Surrounding yourself with a positive group of family and friends in your spare time is the best way to keep a positive and happy outlook on life. People that you can relate to, cry with, be happy with are the best kinds of people. True friends and family are always the best life cheerleaders you can find they are always happy for your achievements, help lift you up when you are feeling down and more importantly are happy if you are happy. You will have your ups and downs with your friends and family but in the end they will love you and will support you until the end.