Keep trying or give up?

Hi I'm 22M and since last year I've been seeing (if that's the right way to say it) a 23F. At the beginning we messaged all day without any problems, but after we went back home (to be clear she visited multiple times her sister in the residence where I live too , that is not in my hometown, I live pretty far both from here and the residence i stay to attend university). Giving only 2 weeks the messages we exchanged went from 50 or more a day to actually 2 or 3 every 2 day or more, I actually asked her if there was something wrong or if something happened, to which she responded that she needs time and if that makes me feel bad we should stop even messaging, maybe i effed up in that moment , being scared to lose another person in my life , giving the fact that I'm pretty much always alone and I have no one i feel comfortable with to open up my self, Yesterday we saw each other again and I hoped we could have talked in private but I found no chance to do it, I wrote her a message while she was out with her sister asking her to stay together a little if she wanted, that ofc was never seen or at least not till now, even though she uses her phone. Now I just don't know what to do, i feel like I should just end things with her ,giving the fact that tomorrow she will go away again and we'll probably not see each other again for 2 months, but I'm doubting everything I think, I'm seeing a psychotherapist and told this story, where he pointed out that something like this should be a big red flag and maybe is just that we are not meant for each other. Still i can't find , like always, a straight point in my head. I'm 90% sure that if I just say " It was a great time but I understand that you want your space and maybe I'm just not the right one for you as you're not the right one for me" I'll just end up in a spiral of depression and loneliness as always cause of my lack of social skills especially with women. I just need advices and of course I'm not thinking that any of you can get me a perfect solution.

Sorry for the long text and for the bad grammar, English is my second language but I find it easier to express my self in it. Thanks even if you just read this.

Have a nice life.