<human>: So, in the past I'd never had that much of an issue with my appearance. I started dating someone- he's amazing. The only issue is after the first year or so (after the initial honeymoon stage), he became virtually uninterested in me sexually. I had gained some weight, so I figured if I'd lost it we'd be back on track. 6 months and 40 pounds later, still nothing. I began buying clothes I knew he'd find attractive, trying to spice things up in the bedroom, and that only led to a 7 month dry spell. Because of all of this, I have virtually no self-esteem. I find myself wanting to look for attention from other guys for validation, but I know if I do I'll feel guilty for it. Don't get me wrong- I'm not doing this to bitch about my boyfriend. He went to the doctors and because he works nights, his sleeping schedule caused his sex drive to diminish. Is there anything I can do to build my self-esteem?

Summarize the given text in a few sentences.
<bot>: My boyfriend lacks sexual interest in me, and I need ways to boost my self-esteem without looking for validation from other guys.