How to cope with a fear of abandonment?

I’m a 22 year old female. I’ve been in my relationship for about 3-4 months now. My partner (male) is 22 turning 23 soon.

My biggest issue I’ve noticed recently is jealousy and neediness. I’ve just been wanting his attention more lately I guess. He struggles with his sleep regulation so he often sleeps during the day… which means we can’t text or talk. I can deal with that usually, although sometimes it’s upsetting since I really want his attention.

Not only that, I’ve noticed lately that I’ve been getting a little jealous when he is with his friend. I don’t care by any means if he has friends… or rather, I WANT him to have friends and a social life aside from me. So I don’t know why it bothers me so much when he talks to his friends and kind of disregards me to some degree. It’s not like he can be in two places at once. There’s also a specific friend that bothers me most: it’s a girl and even though she says she’s lesbian… it just… I don’t know. I get really jealous when He’s with her exclusively. I haven’t said anything to him about this and I don’t think I will because again, I want him to have friends. I won’t isolate him for my own needs.

I honestly believe these feelings stem from a fear of abandonment. I’ve been abandoned a lot throughout my life and usually I’m able to cope with abandonment just fine from platonic relationships… but being in a romantic relationship now (this is my first) just amplifies these fears. What should I do about this? How do I cope with these feelings?

TL;DR
I feel like I’m overly needy for attention from my boyfriend recently and I’m jealous of the time he spends with one of his female (and lesbian) friends. I think these feelings stem from a fear of abandonment and being replaced. How do I cope with this neediness and jealousy? I won’t talk to him about the jealousy because I don’t want his relationship with this friend to change. He needs friends and stuff outside of our relationship.