How do i explain this to her?

so, my boyfriend gets kicked out of his house all the time because his moms boyfriend hates him and his mom pretty much agrees with everything he says, and once I called him at about 2am and i asked him where he was and he said he was sleeping in his car because he had nowhere too go and we live In Michigan so he was probably freezing to death, so of course i told him any time he gets kicked out he can come crash in my room, now i know what you guys are thinking a 17 year old and an 18 year old in a room alone at night that must be trouble but actually all we do is talk and sleep now I'm not saying we haven't had sex but whenever he spends the night all we do is chill. okay so my mom doesn't like him at all,because she thinks he's a bad influence on me because he occasionally smokes weed and I think I've seen him take ecstasy once i think... or and he dropped out of school , but she doesn't know that he pretty much has too support his mom when her boyfriend breaks up with her, by working as a short order cook, %26amp; picking his brother up from school and making sure he's taken care of. I don't think she gets It I've been with my boyfriend for almost 3 years now and I'm still the same person I was before I started dating him. I haven't changed and neither have my morals.How do i explain this to her?
I know this must be a hard situation for you and Im wondering if you have ever considered this from your mother's perspective. Why would she have concerns? Is there any way you can respect your mother's wishes and support your boyfriend at the same time e.g. help him find somewhere to live away from home? It sounds like he is in an awful situation and staying in your room is not going to help him longterm. If you care about him and your mum, you might consider doing what is best for not only both of them, but also what is best for you. All the best!

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