Sick of his job

My husband is starting yet another job after being in his other one for a year. It means yet again he will spend 4 days away training which he always as to do when he starts a new job. He is a sales man and for yrs and yrs he as gone away on and off in all the 22 years we have been together and im sick of it. Our children are all teenagers and do there own thing the youngest is 16. I have no job no friends no family to see so when he goes im all alone and im sick of him changing jobs saying he wants it to work out but I think he only wants it to work out for himself not me and the kids. He said his last job would change things and be more money but nothing changed and the money seemed the same. Hes changing jobs again because it will mean less travelling. I also think he cheats on me when away but I cant prove it. I have never gone off for days at a time like he as and I wish I could to let him see what I have to go through He as never had me away longer then 1 day from the house in 22 years Ive had enough and of the changing of jobs that means days away yet again and no doubt he will leave this job next year and it will happen all over again. Im jealous he gets to stay away and im sick of ferling im taken for granted How do I get out of this life I hate

Thankyou merris for the reply Yes I need a life and I dont want to rely on him for anything whatsoever not even his company. Thats where I have gone wrong and I know if I had friends a life outside the home I wouldn't be bothered about his as much so thats what im going to do. I have met another man behind my husbands back and he as a job that doesn't involve staying away and seems nice but Im not attracted to his looks and i know I shouldnt of met him but I feel lonely