Same woman.
Understand the FEMALE MATING STRATEGY:
1) When she is desirable, she has sex with all the men she wants (usually alphas)
2) When she turns 28ish, she knows time is running out and looks for a beta male to marry and secure resources and stability
3) If possible, she cheats on him with an alpha to secure the best DNA while retaining the beta's resources (cuckolding)