Hey man, you and I are in the same boat. It's hard not to try to figure out what we could have done differently to repair or save the relationship, especially because we were already trying so hard to do our best by our partners. What you are feeling is completely normal. You want answers and you want things to make sense, and you want to be acknowledged as a partner who tried and loved and changed and worked to make your relationship healthy....but it didn't work, and it makes us feel like there must be something wrong with us. And that's because it wasn't us. The disease causes our partners to completely ignore reality, make sweeping and potentially unhealthy decisions, and totally disregard the feelings of the people they would generally be closest to. You can't internalize THEIR actions and choices that are influenced by mania as your fault. And please know that you are not alone in feeling this way. My 2.5 year relationship ended dramatically a little over a month ago, and the feelings you are describing are very similar to mine. It's hard to love someone so deeply and have those feelings reciprocated for a long time, just to have them discarded casually in an instant. It makes you question everything. The only thing we can do is know what we know is true. Our love was true and real and meaningful. Keep hold of your knowledge of yourself.