You can't "breed" 3He; you have to breed tritium, which decays to He3 with a half-life of 12 years. D-3He reactors do produce some neutrons, roughly 1% of the flux of D-T, and almost entirely from D-D side-reactions.
Actually, a big problem with D-3He as of today is the lack of neutrons -- since you only get one neutron per 100 (e.g.) reactions, you can't possibly breed enough tritium to break-even. You have to come up with some other neutron source, or send rockets to Jupiter.
>After a decade, the whole reactor will be nuclear waste.
Fusion reactors are generally made from boron carbide -- a material unique for the fact that it does not become very radioactive when irradiated with neutrons. 14C which is produced can be extracted by oxidation and centrifuging, and in any case is not nearly as scary as, say, 90Sr. No other concerning radioactive isotopes exist with atomic masses between 10 and 21 (cf 22Na).
>commercial helium comes natural gas fields! It's literally a fossil gas, which is why we're running out of it:
Nope, that's 4He. There's basically no 3He in natural gas (because the helium there is radiogenic), so obtaining fuel that way wouldn't work even if we wanted to.