Nice work and perseverance. However, this raises an important point about Blissey as a defender. Blissey is tricky and very time-consuming to prestige against, but is not especially difficult to defeat with full-strength attackers. The half-hour that it took to add your Blissey is probably more time than it would take an enemy attacker to clear all four (or five) Blisseys from the bottom of the gym.
In other words, most of the time, Blissey causes more problems for her own team than for rival teams.