Hi skyblue - so sorry you have been through such a hard time. I don't often venture onto 'relationships' but have also had cancer so I can definitely empathise with how you are feeling.
Firstly - I'll say it to get it out of the way - don't be afraid to ask your GP or onc. about counselling, - the body changes and the emotional stuff you have to deal with during and after cancer are a big deal, yo haven't failed if you ask for help, its a massively out of the ordinary thing to happen in your life, and you'd be pretty unusually if you didn't struggle at some point.
Secondly, the body issues. It is hard to trust your body again, DX can happen so fast you can go from being (so you believe) healthy one week to finding you have a serious illness. It's bound to knock your confidence. But your body has also got you through this illness, you have recovered, so your body has played the part it needed to, to get you through chemo etc.
I have found that things like yoga, swimming, exercise in general have helped me get more in tune with my body and focus on its strengths rather than its weaknesses.
Scars - they are a bastard aren't they? - a constant reminder that you've had cancer, and for a long time you were a 'cancer patient' first and a woman second.
The advice I was given (and I am also heavily scarred) was to take time to just look at my body naked in a full length mirror, in low lighting or candle light at first if it is hard for you to do. Focus on the things than are good, that you like. It may just be small things at first, a certain curve, a shoulder, a hand or foot.
Gradually get to know your 'new' body better and as you become accustomed, i will become easier for you to focus on the positives. Then treat yourself to some feminine undies or lingerie - doesn't have to be overtly 'sexy' - just something that makes you feel pretty and feminine, a pretty cami and matching knickers if you want to be more covered up.
Sex - it sounds as if your Dp is a good man, my DH and I started just with lots of cuddles and loving talking together at night. It took a long time before I got confidence back (and for him too - because he was frightened of hurting me) but it did come back. Chemo and cancer drugs (esp. hormone related ones) can affect your libido in a big way, so that is also something you might be able to talk over with a specialist nurse if you have one, or your GP. (My GP adjusted my drugs slightly, and my nurse suggest various practical things, - sorry if TMI - but things like lubes, that can be used safely after cancer, toys etc)
OK - this is rather along post -so well done if you've managed to read through it. Getting on with life after cancer is a big challenge, an article which I found very helpful is this one you can cherry pick from the sections whatever might be relevant, or read through it all, - I found that he really gets what its like, and kept nodding in agreement!
I've also had some recommendations by a nurse for books about sex which are especially relevant for cancer patients. Not quite sure what I've done with them, but if you'd like the titles, I'll happily have a look for you - might take me a day or two 
Lastly - if you want a support thread, - go onto health there are a group of us calling ourself 'Tamoxifen' (after a beast cancer drug) - we aren't just about breast cancer though - we've been joined by women with various different cancers, including gynae, so we talk about all sorts of stuff, and try to support each other. NO questions TMI, nothing off limits. There's a lot of friendly chat too
- but don't worry if you can't keep up with posts, just dive in, someone will always take time to answer you.
HTH
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