Dilemma

So ladies, I need advice! I'm a pretty average girl who comes from a typical Mexican-American family, &if; you know Mexican-American families, you know that we're tight af! Well, my sister passed away in April of 2015.. after that, my life as i knew it completely changed, my mom sunk into a deep depression but I was not allowed to grieve because I had to pick myself back up & make sure our bills were paid.. I got a second job & kept our head above water.... eventually my mom picked herself back up, secured a job & everything was good. Fast forward to April 2016 when i got into the relationship I'm in now, i couldn't have been happier, it may sound cliché but he gave me a reason to smile again.. we moved pretty fast in our relationship & decided to move in together after only 7mos but things are great and only getting better, HOWEVER....... my mother has now expressed an interest in moving in with us..... my boyfriend and I haven't even lived together a year yet & I feel bad thinking we're just getting started! We still have so much ahead of us & I enjoy my privacy with him! HOW can I express my feelings without offending her?!? P.S. she is perfectly capable in caring for herself, she just doesn't like being alone which I understand but, .....ughhhh I'm just stuck in netween a rock & a hard place😕