Marriage help

My husband asked for a seperation because he said he wants to live alone ...... now him and his brother are moving in together which defeats the whole alone thing ..... we had 2 miscarriages the first one he was as supportive as he could really be and the second i went to the emergency room alone ...... he wasnt happy with the pregnancy...... a few months ago he started acting different saying he wanted to get condoms and all this stupid shit although he knows i want kids we have been together for 7 years .... then he said he wants a seperation which i understand we have been through alot .... we still have sex and its miserable the way he treats me ..... once hes done its back to being distant and i actually asked him today if he is cheating on me again which he said no ..... i love him but its a huge step from space to a seperation he says im home too much but i work47 hours a week! He doesnt have a job he just goes to college ......i cant take much more of the games hes been playing and i dont want to give up on him or leave him hes pushing me away now im starting to detach ...... im scared this will be the end of our marriage