Ok help, men an women but mostly id like a mans point of fiew but all is welcome tanx?

ok iv been wit my man 10yrs we have 2kids since our latest was born 4yrs ago he has lost interest in me we have no life wat so ever which i think is unusual in a man not to ever want it i recently found out he has been sleepin wit men (occacionly)!!!!!!behind my back we tried to work it out i am only 25 im nervous of being on my own after so long but it has made me very ****** up in the head tryin 2deal wit all this im doing my best he says he has changed but every night we get into bed he turns hes back on me if i bring up wat he has done to me r try an talk about it he says im throwing d past in his face which is not true i just feel he needs to show dat he luvs me instead of saying it an actin another way i dont want to be celebit i wud just like other peoples views plz am i bein unreasonable tanx