Governor Baker put in place restrictions as to who is eligible for lodging in MA till May 4.  It restricts lodging to health care workers, first responders, etc.  An is exception is made for the following,

"families or roommates of individuals who are isolating or selfquarantining; but (iii) in each case, for no longer than the period required to complete
the necessary period of self-isolation or self-quarantining"

So if you claim that your roommate is showing symptoms of the virus and you need a place to stay till you work out other accommodations, you should be ok.