When you feeling so unloveable

I've been alone all my life. Never been in a relationship before. But why lately I felt so lonely? Felt so unfair. I've been on couple of dates these past weeks, maybe with 4 or 5 different people. But ended up alone again. Is it me? Is it them?

I wanna feel their "happiness", their "butterflies in my stomach". I would be fine with their "sadness" if i ever felt their "happiness".