It isn’t really about you
Yes, it is your speech, but it’s not about you because it’s neither your birthday nor wedding. Of course, you need to introduce yourself briefly and tell everyone about your relationship with the bride and the couple. But, nobody wants to know anything else about you other than this, so you need to turn your attention to the couple at this point.
Begin with your bestie, the bride
As the maid of honor, you should begin with the bride, who is expected to be close to you, from whose eyes you must have viewed most of the relationship. Talk about what/who you knew your friend to be before she met her boo, and how meeting him changed her life for the better. Focus on the good things, as this is not the time to mention issues they might have had or your misgivings about their relationship.