What should I do? Sorry if it is long but i need help?

ok well i should start at the beginning... my parents got divorced because they didnt love each other anymore. then about 8 months later my dad got a new girlfriend... she is about 10 years younger than my mom, who is 49. My mom was really sad about the new relationship. i mean no matter what he will always be my dad and her ex husband. so anyways i spent some weekends over his house then at my moms. after awhile my dads girlfriend would be there when i was there trying to get to know me more and more! and i just couldnt do it i loved my parents when they were together and i didnt want to give that up. so i was really sarcastic with her but her and my dad really loved each other and they got married after just 9 months of dating. now things got worse i was super mean to her i told her to leave me the hell alone, dont touch me, i cussed at her, and in all very rude and mean. today i still am not ok with her but there is nothing i can do they r married and i should be happy for my dad i love him and i should be ok with what he decides to do. When i was mean to her my dad was really disappointed with me and i didnt like that. i dont know what to do i cant take back anything i said or did but should i apologize?? i dont really feel bad about it but i dont know what to do please help thanks for reading my life pretty much! if u did thanks! please respond!