<human>: It's been nearly a year and a half since I was in a relationship, and I'm starting to feel isolated and worried by it.  I don't seem to be doing anything obviously wrong, but I worry that women don't have interest in me.  Even so, I know this is wrong because I see people smiling at me all the time, or casually flirting with me, but of course, this is different than relationships.

I feel like I spend a lot of time in my head worrying about it, mostly wondering why I haven't been able to meet anyone I've mutually liked over the past year.  It concerns me because I'd like to be with someone, but I don't really see any opportunity for me to meet new people other than via random encounters.

In my past relationships, I've met someone and it's been very natural and did not seem like I've had to force anything.  But sometimes I find myself trying to hit on women, putting myself out there, pushing relationships with women that I can tell aren't interested in me, etc... Basically, I haven't had a "gut feeling" that things felt right in a very, very long time (since my last actual relationship).

The fact that I haven't had that gut feeling, reinforced by my inability to meet anyone that I feel a mutual interest in regularly, concerns me and has started to make me anxious.  People I in relationships tell me that it will happen when it's meant to be, or that I should "just be happy by myself right now."

This makes me feel even worse, and more isolated, because it makes me feel like I am somehow not mentally strong enough to be happy alone.  But when I concentrate on not wanting a relationship, I ironically find myself focusing on it more.

I have a pretty time consuming and occasionally stressful job (PhD student) that I don't really intend to quit anytime soon, but sometimes I want to come home to something other than my thesis.  It's difficult, because all of my friends are in happy relationships, and I find myself feeling empty that I don't have many people to spend time with.

Can you provide a brief overview of the text?
<bot>: looking for advice on what to do to stop focusing on wanting a relationship when you're feeling bad.  How do you not feel bad about wanting one?