I live in Canada, where many moms take 12 mos of parental leave and are then putting their 10-18 mos old in day care for the first time. What I see/hear time and time again is what a difficult transition it is for children at that age. Although leaving a small baby in day care is terrible for Mom (I feel for all of you in the US who only get a few weeks leave), it can be easier for a 3 mos old to adjust than a 1 year old. It will definitely take some time - maybe a LONG time - whether your LO is breastfed or not. Weaning him is likely to only add to his stress levels, not make it easier. I am with the PPs, if a DCP suggested that to me, I'd be ending the interview right there.
Shop around and see what your options are. Some LOs do much better in a home day care, where they get a family-like environment and usually much more TLC and consideration for their personal schedule, and can bond with one caregiver. Others are happier at a centre where they are busy-busy-busy with structured activities all day long.
Unfortunately it's not always so easy as just 'finding someone' and signing a contract, and it's super stressful for everyone. Once you find the right care, it WILL get better!