Mums can be real pains in the ass sometimes, but gotta love them anyways. You really need to stick up for yourself and making plans and following them through is a really really good start! She will get over it, if not, recommend her a good, expencive therapist. No, seriously, mums pull that kind of things all the time. Mine does too... If I'll ever have kids I swear I'll be different.
The bf issue is a hard one, I can see why you are upset. I'd be too. If he wants to keep his personal life and work life seperate, he should honour it by not making you lie about it, in another words not put you in that kind of situation. Maybe you could discuss about it with your other half, I'm sure he feels bad about it too. Work out together how to awoid that in the future. And you need to decide how much you are willing to compromise for the sake of love.
Hugs.