Wow! I went through a period of what you just described, it was odd, and made me worry about what caused it and if I was in any "emotional danger", doc said such stuff happens to some, hormones and changes can be a major cause, and/or life events coming to the foreground of our mind's.
I'm sorry I have no answer to anything,like how to change feeling like this, but want you to know you are not alone.
I bet a lot of our members have this happen, or have been there, it would be interesting to see the next replies your post recieves.
Take care now,
DE