Did my boyfriend ruin my bday?

im 16(15 when this happend) and me and my boyfriend have been together for a month and a half So it was my bday and my boyfriend was hanging out with me that whole day and so me, my boyfriend and my bestfriend was walking and my boyfriends bestfriend(Who is a female he calls his sister) saw him walking with me while she was driving past. So she got mad because he said he couldn't go to tennis practice cause he had to stay home but she saw him with me(Which he did have to stay home but it was shorter then he thought it was gonna be so he spent the rest of the day with me) so she gets mad and texts him saying that he was a lier and hes no better then her old bestfriend(That lied to her all the time) and that he lied to her to spend time with me(She doesn't like me because me and my boyfriend get into a lot of arguements involving her and he tells her about them and she thinks we should break up and stuff.) and so he let me see the text before he read them himself and she mentioned me and i got mad and it upset me and i felt like it was ruining my birthday. So we spend the rest of the day together and he calls me to let me know that he worked it out with his friend and she was sorry but i wanted a personal apology from her so i texted her in a nice civil way asking for an apology and she starts yelling telling me its their business not mine so i call my boyfriend crying and he says hes gonna take care of it but i felt like he was on her side. So he talks to her and she decides they shouldn't be friends anymore so he got mad at me and i cried myself to sleep over a friends house. So did he ruin my birthday or was it both of them?