How can I be cool with my boy friends mom?

Destiny
Disclaimer: I'm a introvert to the T and sometimes it's hard for me to make friends and start simple conversations. 
  I've been with my boyfriend for almost a year now. We're great and he treats me with so much love and respect. His mom is super nice too and seems to really like me and sometimes try to start conversation with me but almost every time, I either freeze up and let that awkward silence seep in or I'll run to my bf & see what he's doing just to escape the nervousness. It's not right and I see that. I just don't know how to approach her or just build a relationship with her! We both like similar things and I wanna have the relationship with her where we can do things together just us and her being like my second mom but I just can not get over this awkward jump I always feel to even initiate a conversation via text, phone call or in person. It just seems weird to me but I know it shouldn't be like that. Can anyone help me out?! 😩🙏🏽 
Thanks!