Step father needs help big time!!!?

I am 28 yrs old I married my wife 3 yrs ago who is 15 yrs older than me. We lived alone for the 1st almost 2yrs of our marriage (1yr we did a tour in Iraq together) we now have 3 of her children living with us 16 an 22yrs old (females) and just recently her younger son 23yrs old. I am in the army still now she did her time and got out now she goes to college full time. I work from approximately 5am until 5:30 pm. over the past couple of months we have not even been sleeping in the same bed. I have been diagnosed with PTSD (Post Traumatic Stress Syndrome) and am currently going through therapy. Now it was my idea to take in her 22yr old and (who by the way has 3 kids of her own) and yes they live with us too. I did that so she could have a better life she has been going to full time college and is near to finishing her degree for nursing.

I have for the longest time been paying nearly every single bill in order to help improve my wife's horrible credit...only now it is my credit that is starting to take the hits i have been paying out so much i barely have 2 dimes to rub together. Now that you know all of that yesterday i checked the phone bill and saw that my wife has been texting a strange number at all odd hours day, night 1 sometimes 3 am.

I have refused to help out around the house as far cleaning and what not and today am going to give a break down of the bills to everyone showing that myself and the wife will each pay 1/3 while i expect the other three kids to pay 1/3 is there anything else i should or should not be doing any advice would help please and thank you.