<human>: Summarize the given text in a few sentences.

So recently, my friend (who's also an ex) just got out of a relationship gone bad/stale.  We started spending more time together and just had regular ol' fun, which was great because I don't have much friends to begin with. I'm 30, she's 26. We dated for a year and a half, give or take a month a couple of years ago. 

But now she told me she just started seeing someone. And this bothers me, and I don't know why. I'm feeling... jealous, if that makes sense. I'm actually feeling quite distraught by this.

My ever self-doubting and over analyzing mind came up with several possibilities.

- I'm in love with her all over again and don't know it yet.
- Not in love but more a feeling of nostalgia, to the time when we were dating, "caused" by the time we spent together these last few months.
- I'm afraid that, with her having someone new in her life, she won't have time for me anymore. ( I actually confessed this to her, and it's incredibly selfish, I know... ) 
- or a combination of (all of) the above.

What do I do? Do I tell her?

I'm afraid of either ruining our friendship, which I hold very dear, or her chance on newfound happiness.
<bot>: Why does it bother me that my best ladyfriend (also ex-girlfriend) found new love... Am I in love with her?