Problem with daughter in law?

I am devastated and need to share my story and seek advise . About two years ago after knowing his girlfriend for only 2 weeks my son went on a holiday with my husband and my daughter to Europe and staid in touch with his girlfriend On a day he returned I arranged party and she was there too beautiful and lovely and they wore so cute together it was a pleasure seeing them together after that she often staid in our house the night and some times even for few day we all adored her then about four weeks later they told us she was pregnant and even thought we felt he was too young only just turned 18 day before his return from Europe we wore supportive and she was also only just over a year older then him but still too young and we felt they don't know each other well enough we decided that we will support them after all we love our son and we will do anything for him , we wore going to be grandparents , maybe sooner then we expected but with our support we thought our son and his girlfriend will be able to still finish university. My shows up with her soon after saying her mum kicked her out of home and she has no where to stay could she stay with as for a little while till she figures out what to do . My husband and I agreed and the same day she moved in . I felt so sorry for her what she told me about her mum and family in general I just wanted to give her as much love and attention to at least try to make her feel better . She was kind and friendly we accepted her us our own . Sadly they lost the baby and it was just sad and unpleasant time for all and most of all for her . No long after we had my cousin and her husband move in with us and my sons girlfriend still friendly with as became more and more sad , She still complained about her family that wore giving her hard time she left school saying she only did that because her mum wanted her to be a nurse she wanted something else she didn't want to live her mum's dream . I loved her and was feeling great sadness for her her according to her story everyone gave her hard time disrespected her ,gave her hard time . She didn't know her father she wanted to write to him but didn't know how and was worried he will ignore or refuse her . My home was fool of people and all I did was cook clean after everyone go to work come home and it wasn't easy she was sad now all the time I was there for her even thought at times it was all too much for me I was there for them . My cousin cooked 5 times in three moths she lived with as my daughter in law 4 times in eight moths that she lived with as . and even when they were cooking it was after me to serve and wash up no one ever did anything and I newer complained I simply sometimes had to live some work for next day or just do things at night . When she was sad and crying my son would come to me asking to please talk to her I always left everything as I would for any of my kids to talk to her . Then I noticed that more and more often she stays in their room when my son is not there but when with us she would still be sweet and polite so I assumed she has problems with her mum , she has started seeing her mum and other family again by that time but was still complaining about them allot I was there when she wanted to talk but when she closes her self in a room or it didn't seem to me as she is willing to talk after I asked if everything is OK I backed off just as I do with my own kids thinking she will talk if she needs to . First valentines day I paid for a weekend away for her and my son and that morning before leaving for work I left box of chocolates for them she sent message when she woke up to me saying how lucky they both are to have me and my husband in their life and how she wishes her family is more like that . I remember thinking after reading that sms how lucky I am I already have three perfect children and now my future daughter in law so kind and lovely as well all hard work didn't seem so bad . Little did I know that all this time wile I was thinking how perfect everything was she has capt my son up late most of the night crying she wanted to move out weekend way that I arranged for then she used to fight with him for not wanting to move out , my son was worried he did have a job but since he is so young his pay is only small he didn't feel his ready at home they had free food free roof over their had what they earn was for their own pleasure he wanted to enjoy that as long as possible . Then one day he told as that his living we said you not a prisoners here if you want to move out fine if it doesn't work you can always come back but seeing him cry I we also said you don't have to it is up to you . We wore sad but we help them . But she changed from that tha