<human>: Give me the gist of the text in a nutshell

Background: Me and my boyfriend have known each other for 8 years, and have been together, in an open relationship for two of those years. This has worked well for us, but in recent time, I've felt like he's been needlessly clingy and jealous (not of sexual partners, but more a fear of mutual friends being romantically interested - specifically my best friend who recently moved back into the country after a promotion), and when I brought it up he told me that I'm making him feel insecure and that he's overcompensating because of it. 

I'm currently in university studying to become a doctor of medicine, spend my weekends helping the homeless, and have traveled the globe for the better part (2 months, not consecutivley) of this year with friends. 

He's dropped out of high-school a couple of years back and have been unemployed since then, due to some drug-charges making it hard to find work. This means that he has a lot of time on his hands, while I do not, and he told me that the fact that I am constantly busy is making him feel unappreciated, and serves as a constant reminder that he lacks direction in life, furthering his insecurities and is making him clingier.

Further, he's told me that his height (5"5) and weight (120 pounds) are factors that make him feel like he's undeservant of me, an objectivley quite attractive girl, and that the fact that he thinks I can do better is making him jealous and even more insecure. To be fair, although I've never stated it, this is something that has also impacted our sex-life, as it does make me feel less attracted to him, but I hoped it wasn't noticeable.

(We have sex around 3 times a week, although I'm never super-excited about it)

So, what can I do to make him feel less insecure? And is there anything I can do to maybe make me feel more attracted to him, so the physical aspect (which might be my fault) stops being a problem?
<bot>: Boyfriend says I'm making him feel insecure, physically and in relation to work/school, and it's making him jealous / clingy. What can I do?